Good Adultery, Bad Adultery

Adultery in fiction is very much a mixed bag. Sometimes you have good adulterers; sometimes you have bad adulterers. Those you see as 'just messing up' and can be sympathised with, and those who are genuine Jerkasses and deserve to be caught and humiliated in front of a large crowd.

On a superficial level, in fact, the distinction between good adulterers and bad can be entirely arbitrary. Most good writing, however, takes clarity and nuance into account.

Adultery, good or bad, is Not to Be Confused With open relationships where the partners are honest with each other and not in an abusive way.

Some sure-fire signs that someone is a 'good' adulterer:
 * The adulterer is the protagonist.
 * Their partner is physically and/or emotionally abusive, to the point that they may well kill a partner whom they discover is cheating. Or even just for the insurance money.
 * The relationship being "ruined" is quite literally loveless. The cheater was forced into the arrangement, either against their will, or as a guarantee to keep something terrible from happening to a loved one.
 * For the sake of the One True Pairing. Especially obvious if the adulterer and the adulteree are both long-term characters, but the individual being cheated on is only in the show at all because they are married to one of the adulterers.
 * A couple still love each other but they are going through a rough spot, or they are 'on a break'. However the original relationship is not over over, so it's still portrayed as a kind of infidelity. Obviously this has a tendency to make the situation worse. Loneliness is often a huge factor in the cheater's motivations.
 * The cheating is with a member of the same sex.

Signs that a person is a 'bad' adulterer:
 * The person being cheated on is the protagonist.
 * Sheer shallowness. Rather than giving any actual reason for an affair, they just do it because it feels good.
 * In spite of the fact that they're cheating, they have no moral compunction about manipulating their partner for their own ends.
 * Plain old dishonesty. Oftentimes, if a character is involved in an open relationship or is simply dating casually, having multiple partners isn't really a big deal. What really sets off the person being cheated on, though, is being lied to. Claiming to have an exclusive relationship, while actually not, is a guaranteed Berserk Button if the scorned lover finds out.
 * When the cheated-on character is dealing with heavy stress brought about because of the marriage, and the affair further aggravates it.
 * The cheating in general is meant to provoke discomfort in the form of sexual jealousy in the audience—see Netorare Genre.

See also The Unfair Sex, where the distinction seems to fall across the Gender line (but may also use the above to justify it).

A lot of this probably stems from the fact that adultery in Real Life is complex and difficult; while people cheat for many reasons (some understandable and sympathetic, others less so), it's still considered a betrayal of the other partner in the relationship. In fiction, however, the adulterer is often treated as either Good or Bad—there's rarely much grey in-between.

Anime and Manga

 * In Chobits, Hideki's cram school teacher is discovered having an affair with Hideki's best friend Shimbo. When Hideki realises the implications that she's cheating on her husband, he immediately starts calling Shimbo a wife-stealing pig... until it's revealed that her marriage is completely devoid of any emotion, as, shortly after they married, Ms Shimizu's husband bought a persocom and fell in love with it, completely forgetting about her. It got to the point that she couldn't get into her house anymore because he'd put the chain on the door, showing that he'd forgotten she was even coming home. Under these circumstances, it's understandable as to why she'd have an affair, and since Japan does not have a good attitude toward divorce she might not have thought she could just divorce the guy, especially if the marriage was not arranged and they married ostensibly for love. And as a teacher she has to appear morally beyond reproach.
 * Lampshaded in Planetes. Goro Hoshino is all but married to space, and spends years away from Earth. His wife very pointedly mentions how he's extremely lucky to have her, because she should have gotten into an affair by now, and anyone else would have. Goro himself agrees.

Fan Works

 * In Sailor Moon fanfics that feature Usagi/Seiya and are set during Stars or after, Usagi will usually cheat on Mamoru if he's alive at any point because she's lonely and thinks he's ignoring her or because he's come back and is a complete asshole - often Mamoru is cheating on her as well. This is almost always portrayed as right and just because Mamoru is just SOOO mean and abusive.
 * Mamoru cheating on Usagi is also almost universally used as a way to show what a horrible person he is, making it a case of bad adultery. If he's not sleeping with Rei, it's Setsuna, An, or whomever else the author can twist to Make Usagi fall totally for Seiya, Haruka, or Demand, making it good adultery.
 * Used rather inexplicably in the widely read Avatar: The Last Airbender fan-comic How I Became Yours. Fire Lord Zuko getting Katara pregnant and physically assaulting his betrothed (Mai) for getting upset about it okay because Mai's evil now and we're not supposed to side with the bad guys.

Film

 * American Beauty plays with this: The protagonist, a middle-aged married man, . Later,  but once , he reacts by treating her warmly and with care.
 * In Braveheart, the English have quite a few bad cheaters, with their lords raping married (and non-married) Scottish women, and King Longshanks' sniveling son having an obvious affair while ignoring the needs of his wife, Princess Isabella—not to mention implication that the only way Isabella would produce an heir would be for Longshanks to do the honors himself. On the other hand, Isabella then has a romantic affair with the heroic Scottish rebel William Wallace,.
 * Titanic: Rose is a Lonely Rich Kid who is loveless and unfulfilled in her relationship with Cal, which was organized by her mother for money, and is therefore justified to the audience in cheating with Closer to Earth Jack. Cal is initially portrayed as clueless regarding Rose's feelings, but as the movie goes on, he loses any possible audience sympathy by turning into a violent Jerkass.
 * The Bridges of Madison County - which, oddly enough, doesn't actually fit any of the aforementioned criteria for "good adultery". Then again, if the other man is Clint Eastwood, nobody's gonna blame you for not being able to measure up.
 * The print comic Doonesbury mocks this movie, by having JJ leave Mike for Zeke under similar circumstances... except Zeke is depicted as a buffoon and JJ a flighty fool who made a stupid, spur-of-the-moment decision without thinking.
 * In Coming Home, the wife is lonely and unsatisfied, the husband is distant (and by the end of the film, crazy) and the paraplegic Vietnam veteran with whom the wife cheats is kind and noble. (The vet is also able to help the wife reach orgasm, something she could never do with her husband.) It almost seems at one point as if the main message behind the film (apart from "War Is Bad!") is that "Adultery Can Be Good for You!" Of course, the infidelity does have negative consequences... but mostly for the husband. One gets the impression that the wife is better off for the experience.
 * Chicago has this all over the board. The earliest instance is where Roxie cheats on her dull but loving husband Amos, then kills her lover in a rage, and continues to manipulate Amos to the end despite his continued loyalty. Amos is also one of the the only sympathetic characters in the whole movie, next to the wrongly-executed Hungarian woman, and this trope is lampshaded in his solo.
 * In-universe, Velma discovers her husband cheating on her with her sister and kills them both. This is meant to highlight just what a Crapsack World they were dealing with. All the other inmates, by contrast, seem to feel justified in murdering their husbands- and are not generally considered to be very good people.
 * Doctor Zhivago stars a pair of lovers who are themselves married to other people. The woman's husband disappeared in a battle during the War, and she spends much of the movie trying to find him. The man's wife...well, nothing happened to her actually. She still loves him and lives with him at the time of the affair and is even caring for their child. Because the movie is pitched to the audience as being about one of the great love stories of all time, the fact that this is technically adultery is nearly an afterthought.
 * In the 1989 film Cousins, where a man's wife cheats on him with another man. Where it gets interesting is that the man who was cheated on falls in love with the cheater's wife. Both the main character's wife and her lover are shown to be...not great; both the main character and his lover are shown to be just wanting more.
 * In Liar Liar, amoral lawyer (Jim Carrey) convinces his adulterous client (Jennifer Tilly) to believe that she was driven into the arms of another man, in spite the mountain of evidence that she's just a slut. This is played for laughs until the end, at which point the Carrey character feels great remorse for winning the case and possibly robbing the husband—a loving father—of custody of his children.
 * Five Minutes to Live portrays a man cheating on his wife as bad, but we still are meant to like him. Her loyalty, meanwhile, is unswerving, even in the face of Johnny Cash. Johnny Cash, people (okay, he plays a maniac who'd just as happily kill her as bed her, but still)! Needless to say, the movie ends with their marriage being completely patched up.
 * Spanglish. Adam Sandler's character is the one left sexually unsatisfied due to how quickly his wife gets off (and subsequently falls asleep). Later on, when she is discovered to be a cheater, she is villified. Meanwhile, his affections for the Latina maid is justified in much the way that the typical "woman finds love out of marriage" is, but they are both strong enough to realize that they can't have what they want.
 * Same Time Next Year has Alan Alda and Ellen Burstyn as two lovers who meet once a year at a particular resort to spend a weekend together, before going home to their spouses for the other 51 weeks. This goes on for many years. We never see or hear the other spouses, and apparently these two love each other even though they also love their spouse as well.
 * Terms of Endearment follows Emma (Debra Winger) as a kooky-but-lovable girl who early on marries Flap (Jeff Daniels) and gives up her career to do so. She meets John Lithgow, and grows sympathetic to his cause—his wife has an injury which prevents the two from having sex (although this may be an excuse on the wife's part). Meanwhile, Emma is growing emotionally distant from her husband, who became a professor while she had to stay at home to take care of their children (they met in Grad school). Emma admits to Lithgow that she's not sure whether Flap's cheating on her, but considers this a stronger justification for the affair, since she's not just doing it for Revenge Sex. When she does discover that Flap's cheating on her with one of his students, she flips out on him on campus and demands a divorce. Later, she does not tell him about her affair with John Lithgow  even though she considers it, in part because of the obvious problems it would create ethically afterwards.
 * Entirely averted in the British World War II film Brief Encounter, where two married people meet on a train, and realize they're each other's soulmate. But they end up giving each other up to remain loyal to their own home lives, and this is portrayed as the right thing to do.
 * Also averted in the cinema-verite musical "Once" (which has a lot in common with "Brief Encounter"), where the Girl refuses to have anything other than a platonic relationship with the Guy: while she and her husband are separated, and the marriage is probably unsalvageable, she wants to give it every chance she can, for the sake of her daughter.
 * Averted in Casablanca as well. Ilsa is arguably the love of Rick's life, and she seems willing to leave her husband Victor Laszlo for him if he asks. However, in the end, Rick decides that the right thing is to leave Ilsa and Laszlo—who are actually quite Happily Married—together.
 * Used in Dodsworth. Throughout the main part of the film, the wife, desperate to feel young, wealthy and attractive, pursues other men and lashes out at her husband whenever he implies any impropriety on her part; the film makes an effort to understand her state of mind, but she's still unsympathetic. The husband, meanwhile, winds up leaving her in the end for a much nicer woman, and it plays out as a triumphant moment.
 * A Fish Called Wanda; Archie is depicted sympathetically, while his wife (and daughter!) are both horrid monsters. In the end he runs off to South America with Wanda without a backward glance. Wanda, on the other hand, is depicted as a conniving, materialistic shrew, manipulating everyone until the end . Sure, she wasn't all that happy that, but that didn't change what she was about to do.
 * Peter Sellers comedies have all sorts of takes on adultery:
 * In The Dock Brief (1962) he plays a lawyer trying to defend a client who openly admits to killing his wife. The meek fellow (Richard Attenborough) hoped his boisterous wife would have an affair with a boarder whose personality better suited hers, but finds out she didn't because she respected the sanctity of marriage too much. He snapped and killed her right then and there.
 * Waltz of the Toreadors (1962) has Sellers as a womanizing general married to a cruel woman who feigns illness and threatens suicide to try to keep him from pursuing other women, as revenge for his past indiscretions—and she wasn't always faithful to him either. At the end, circumstances keep him trapped in the marriage when he makes an I Want My Beloved to Be Happy decision regarding the mistress he truly loved, and he is about to commit suicide - then he meets the new maid...
 * Only Two Can Play (1962) has Sellers' character trying and failing to consummate an affair with another (married) woman out of ennui with his current life with wife and kids. His wife chews him out over this when she finds out, but says he can do what he wants; it seems she's bothered more by his secrecy. Realizing the other woman doesn't really care for him, he returns to his wife and learns she had an affair with the other's husband during all this! They reconcile.
 * One likely reason Inspector Clouseau turned into the Breakout Character in the original The Pink Panther (1963) was not only because his wife was cheating on him with the jewel thief he was pursuing, but because at the end she helps frame the poor Fool for their crimes...making him more sympathetic than intended. It helps that the movie clearly sets his wife as being in the wrong. Clouseau is shown to be extremely devoted to his wife and willing to indulge pretty much any of her whim, and never shows any interest towards the other gorgeous women in the movie. Sure, he's a klutz, but no one can fault his devotion as a husband.
 * In What's New, Pussycat? Sellers is a deranged psychiatrist whose wife, a stereotypical fat lady opera singer, accuses him of being 'a lascivious adulterer'. He angrily replies "Don't you dare call me that again until I've had a chance to look it up!" When patient Peter O'Toole asks for help to stop his womanizing ways for his impending marriage, Sellers merely suggests he get married and cheat.
 * In I Love You Alice B. Toklas! (1968), Sellers becomes a Runaway Groom twice—the affair he has turns out to be unfulfilling—as he tries to figure out what he really wants in life.
 * In Being There, Eve Rand falls for Chance (Sellers). She's married to another man, Ben, but it's a May–December relationship (with what author Ellen Gilchrist called the "bartered sexuality" that implies in an essay) and in fact, he's dying. But first, she loves Ben dearly and he her. Second, Ben senses and understands her longing for Chance, and in fact it makes him happy that she'll have someone to love and to love her when he's gone. With this understood, she makes several seduction attempts on Chance, and Hilarity Ensues since Chance hasn't the faintest idea what's going on. At the end, however,
 * One growing variation of this trope, appearing in recent films such as Waitress and Before the Rains, is a woman with an abusive husband having an affair with a man whose wife is the nicest person ever. Before the Rains has the man taking advantage of the woman, who is trapped by her society. Waitress treats the man slightly more sympathetically, but has the woman end the affair due to an attack of conscience after she meets his wife, and also after she leaves her husband.
 * John Tucker Must Die has three high school girls who find out that the titular John Tucker is going out with all of them at once. Cue them attempting to do horrible things to him. A good establishment of the "don't you dare lie to me" clause- Tucker went to a highly elaborate effort to make sure that none of his girlfriends found out about the other. As opposed to, say, simply telling him they weren't dating exclusively.
 * Compare She's Gotta Have It, which features Nola dating three different men simultaneously. They're all mildly resentful of the situation- but it never explodes into an Escalating War in part because Nola is honest with them from the beginning what the situation is.
 * The Whole Nine Yards has the husband, Oz, working his tail off to support his unloving, freeloading wife AND mother-in-law, while they're plotting to have him killed for life insurance. She also goads him into trying to turn another hitman, Jimmy, in for reward money showing a clear lack of concern for Oz's well being in the process. When Oz starts courting the Jimmy's ex, nobody is feeling sorry for the wife. In fact,
 * Little Children fits this mold as well. Sarah's husband is shown to be rather perverse, using internet pornography and fetishes to get his kicks and ignoring Sarah's emotional and sexual needs; so her cheating on him may be seen as acceptable. Brad, however, is a stay-at-home father who seems to have latent resentment over his wife's control over the money, and run of the household. But, Brad's wife does not commit any major indescretions against him, with the exception of being somewhat distant to his feelings of personal inadequacies; so Brad cheating on her is somewhat less sympathetic. However, one of the central themes of the film is the fact that basically good people can do very bad things, and that social mores and values often don't factor in well in real world situations.
 * The nature of this trope is an important point in Stanley Kubrick's Eyes Wide Shut. In a discussion about the motivations of men and women cheating on one another, Bill Harford asserts that "women essentially just don't think that way." Whereupon his wife replies "If you men only knew...." and proceeds to tell him of one occasion on which she nearly cheated on him for reasons which are not in any way sympathetic. The confession haunts Harford throughout the film, inspiring some decidedly reckless actions on his part.
 * Done in Now, Voyager, when Jerry Durrance cheats on his wife (who "isn't good for him") with Charlotte Vale, and the affair is portrayed as freeing and empowering for him.
 * Played with all over the board Mean Girls. The guy, Aaron, is arguably the only one portrayed as totally in the right. His ex-girlfriend, Regina got together with him again just because the main character, Cady wanted him, but it's later revealed that Regina has been cheating on Aaron. After the Escalating War ensued, Cady revealed this to Aaron, hoping to steal him for herself. Soon enough, Cady becomes the new "Queen Bee" and she later revealed that she'd been trying to get a chance to talk to Aaron in private, because she thought Aaron was Regina's property, and that she wasn't allowed to talk to him. At this point Aaron just walked away from the whole messed-up situation.
 * In the Irish film Intermission, a middle-aged banker named Sam leaves his wife of fourteen years, Noeleen, for the younger Deidre (who is broken up from her own relationship to Unlucky Everydude John). Sam's rationale is that he and Deirdre "just clicked" while leaving Noeleen enraged and questioning her worth as a woman and wife. It's kind of hard to feel very sympathetic for Sam and Deirdre, as Sam did leave his wife without any warning and without even divorcing her first, while Deirdre doesn't even seem to contemplate her actions. Deirdre's jaded sister does frequently call them out on it though. In the end, Noeleen takes Sam back, but isn't going to be letting him forget his little transgression anytime soon, while Deirdre realizes that John really loved her and they're engaged by the end.
 * Although none of the female characters in Miss Pettigrew Lives for a Day are actually married, they are frequently adulterous on their partners; however, their actions are generally presented in a negative light. Delysia is overall a sympathetic and likeable character, but it's made clear that her stringing along of three men for her own purposes is cynical, manipulative, and ultimately harmful as she's destroying her only real chance for happiness. Edythe, meanwhile, is shown as a selfishly opportunistic harpy, mostly because her affair seems to be entirely random while Delysia's are used to make her position in life more secure. One of the major themes of the movie is how tenuous successful women's positions are, and how much they rely on the men around them, so both characters can be seen as sympathetic.
 * Tyler Perry's The Family That Preys. Andrea is constantly cheating on her husband with her boss William. Her husband loves her and only wants to help provide the income along with her. She berates him, humiliates him, and is potrayed completely unsympathetically as she tries to get closer to William who is a CEO and
 * Used in Walk the Line, when Johnny Cash is distant and generally a dick to his first wife, while openly pursuing June Carter who, by contrast, is entirely unwilling to betray her husband. But he's portrayed sypathetically, and has a Crowning Moment of Heartwarming when he finally winds up with her. He *is* Johnny freaking Cash though.
 * In Frida, Frida de Kahlo is okay with her husband Diego Rivera's infidelities, as she comes from a period and culture that accepts that a man has 'needs.' (She also sleeps around herself.) What she makes him promise, though, is that he doesn't betray her. Later on, guess what his sleeping with her sister counts as?
 * The entire film of It's Complicated is one big hypocritical example of this trope.
 * The Mike Judge film Extract has the lead character hire a young pool boy to seduce his wife while he was drunk and (unwittingly) under the influence of heavy drugs, just so he feels morally justified in sleeping with the new, attractive, younger girl at work due to feeling sexually unsatisfied and realizing that his wife is losing interest in him. Once he sobers up he decides against the Zany Scheme at the last minute  As for that new girl at work   All of this is played sympathetically, and it turns out that  So while he's certainly no saint, he's also not quite an irredeemable bastard either.
 * Francois the title character of The Tall Blond Man With One Black Shoe is having an affair with his best friend's wife (all three in the same orchestra) - he's made out to be sympathetic as he'd like to terminate it, but is too weak-willed to resist her aggressive advances.
 * Lifetime movies often use this theme. And guess who is the "good" adulterer and the "bad" adulterer...
 * The main plot of The Descendants is George Clooney finding out that his wife, who was recently put into a coma, had cheated on him for a long time. When he confronts her friends about the affair, the female friend tries to justify the cheating, at one point saying, "It wasn't her fault...." Clooney immediately shuts down that line of conversation, saying, "You're talking to me in cliches? It's never the woman's fault? Give me a break!" While the movie does suggest that her motives were not unsympathetic and that Clooney's character had his part to play in the breaking-down of their marriage, it's still made clear that her affair was selfish and destructive to her family.

Literature

 * Kate Chopin's The Awakening has the protagonist, Edna, is married to one man, in love with another, and having sex with a third (who admittedly probably doesn't care about the other two). And she pretty much tells the second man that she won't let any man control her, implying that she pretty much intends to keep things this way. It's hard to tell how sympathetic she's supposed to be. This also pops up in some of the author's other works.
 * Naturally Anna Karenina's main plot is Anna's morally ambiguous adultery. Although at first the loveless marriage excuse comes up, Anna later claims to have fallen in love with her husband again, and he expresses similar feelings. This does not stop her affair with Vronsky. Whether her hedonism is good or bad is left in an incredibly gray area- while Tolstoy suggests that her society is forcing most people to be repressed and unhappy, and that Anna is too passionate a woman to put up with it, he also shows her leaving her son with his angry, oppressive father, and of course, committing suicide.
 * Used in Jane Eyre, where the cheating husband's wife (who he was arranged to marry, thought he was in love with her, unaware of her insanity) is a lunatic who tries to kill him multiple times. He is so ashamed that he keeps her locked in the attic and never lets the public know of his wife.
 * This is Older Than Print. In Geoff Chaucer's The Canterbury Tales, the Miller's tale, a landlord's (John) very attractive wife (Alison) cheats on him with a student (Nicholas), by whom convinces John that an essential second flooding of the world akin to Noah's Ark would happen again, the husband whom prepares for all three of them by the man's instructions (suspend tubs from the rafters, go in one and cut them loose when the water high enough), while the two have sex. Meanwhile, a parish clerk (Absolon) is also attracted to the wife, believes John is away, and asks her for a kiss from outside the 'privy vent' of the house where this is all taking place. The wife pretends to put her head out to kiss him, but since it's really dark, he ends up kissing her ass. Angered, he returns with a hot coulter (blacksmithing tool) to ask her to kiss her again, but Nicholas sticks his butt out now and farts in his face. Absolon strikes him and burns his rear, to which Nicholas calls for "Water!" in his pain. John believes that someone has seen the flood and cuts the tubs loose, but breaks his arm in the fall, as there is no water. Nicholas is burned on his buttocks, Absolon is personally humiliated by Alison and John, aside from the broken arm, is seen as a madman while trying to explain his reasoning to his actions and is a 'cuckold' (A man married to an adulterous wife). Pretty much nothing negative happens to Alison, at all, but the Husband is definitely portrayed as not only unreasonably jealous (and thus had it coming), but too dumb to be sympathized for, because every Christian of the period knew that God had promised there would not be another great flood, and therefore he should have been able to see through it.
 * D.H. Lawrence's Lady Chatterley's Lover. Lawrence himself bemoans how beastly the whole situation makes the titular character and Connie Chatterley herself look from a certain perspective, but he kept the story that way because that was how it turned out. But Clifford, the cuckold, could be interpreted as an Author Avatar due to how Lawrence was impotent due to having tuberculosis and his wife was cheating on him, which gives the sympathetic portrayal of Connie's cheating a more personal reason for it's presence.
 * Used in Edith Wharton's Ethan Frome, in which Ethan is portrayed sympathetically as being trapped in a loveless marriage to Zeena, a hypochondriac shrew, with his only chance of escape from Zeena and the confining town of Starkfield being the vibrant Mattie. In the end, though,
 * This trope makes a surprise appearance in Daphne du Maurier's Rebecca, in which . We also find out that
 * Used in the Incarnations of Immortality series. The Incarnation of Death (who is new to the position) checks his mail and finds a letter that reads: "Dear Death--Last night I caught my old goat cheating again. I want you should take him out right away so that I can get the insurance. Sincerely, Outraged Wife. PS, Make sure it hurts!" Death is repelled by this request for murder, thinking to himself, "No need to answer that one. No wonder the old goat cheated!"
 * Occurs in a good 75% of John Updike's total fictional output; the adulterous male protagonists tend to be portrayed as essentially sympathetic, if deluded, in their desire for something more out of life, even when it leads to their treating their families like dirt; any female adulterer who isn't sleeping with the hero tends to be silly, desperate, bitchy, or just doing it for revenge (and some of them manage to be all four at once).
 * Husband and wife Leino and Pekka in Harry Turtledove's Darkness series. When sent onto separate isolated teams to work on top secret government projects, both of them end up committing adultery. While the text itself doesn't make any moral judgments in Turtledove's signature style, the respective situations definitely make the wife Pekka the more sympathetic of the two. Her affair is with someone who has also been a major character from the beginning of the series, who we have come to like for his quick wit and ability to make it out of some dire situations, plus she agonizes over her growing feelings toward him for months before they finally hook up. Leino, meanwhile, almost immediately jumps in the sack with a shrill harpy who has nothing going for her besides her looks, and they're both killed at the beginning of the final book.
 * Pekka later becomes violently distraught with guilt over her infidelity for a time, and when she eventually learned of her husband's dalliance, and accepts it with a "at least he didn't die alone" outlook.
 * In Turtledove's Worldwar series, focus character Sam Yeager ends up having sex with the married Barbara Larsen in a "we're going to die, so why not?" moment. When the moment wears off, both parties are angry and ashamed that they let it happen, but Barbara remains faithful to her husband. This isn't really portrayed as good or bad, just something that happened that wouldn't have under normal circumstances, and the two try to mend their friendship afterwards. But when they find out Barbara's pregnant and are told (wrongly) that her husband is dead, she and Sam get married. When the husband does return, this is only the latest step in a Humiliation Conga that leads to him going off the deep end and eventually being gunned down by the military. Much later in life, when Yeager tells the whole story to his son Johnathan, he confides that he believed Barbara would never have stayed with him if not for the pregnancy.
 * John Fowles' The French Lieutenant's Woman, where the male lead Charles' difficulty in choosing between the nice but shallow and socially confined Tina and the bold, exciting Sarah is treated sympathetically. And without actively demonizing Tina to boot.
 * Played with in Graham Greene's The Complaisant Lover. We're led to believe Mary's having an affair to escape the confines of marriage to dull, buffoonish Victor. When he finds out about the relationship, he shows himself to be a decent, sensitive man- and Mary and her lover look worse and worse by comparison.
 * Used in The Curious Incident of the Dog in the Night-Time. Her sympathy, overall, is hard to gauge.
 * Used in The Horse Whisperer in which Annie commits adultery because she's fallen in love with Tom Booker. The two of them are portrayed as nothing but sympathetic, despite the fact that Annie's deeply distressed daughter Grace is involved. Somewhat averted in that Annie's husband is a nice guy, and that Tom.
 * In Michael Chrichton's Next, a female scientist is clued into her husbands affair by her sapient parrot (who probably did it on purpose) and flips out on him over it. A page or two later, she's in the arms of her lover, who she's been seeing for over a year. Uh... huh.
 * In Ayn Rand's Atlas Shrugged, Lillian Rearden discovers that her husband Hank is having an affair, and since she thinks it's some casual fling with some floozy, she doesn't think twice of it as she believes it demeans both her husband and his lover, so she admits that she will neither divorce him nor tell him to break it off. But when she discovers whom he's having the affair with:, and that it's a mutually rewarding relationship, she becomes horribly upset and tries to demand he stop it. She eventually has a thoroughly repulsive one-night stand with James Taggart solely for the purpose of demeaning Hank. She's not happy when she reveals her infidelity to him and realizes that he doesn't give a damn.
 * See also: Real Life examples below.
 * The Naked Husband by Mark D'Arbanville spends a whole book exploring this trope. He and his wife had developed distance without realising it during their marriage, and his attempts to decrease it are generally met with rejection by his wife. His affair with a woman he met at work is shown to be extremely passionate, and it is obvious they are soulmates. However, the damage the affair causes to their respective spouses and families is shown rather vividly. I would call it one of the most ambiguous books on adultery ever written, and very good for it. Of course, given the author's personal experience it might have been expected...
 * Used in The Girl With the Dragon Tattoo by Stieg Larsson. Features the good cheating as in everybody in the relationship knows about the relationship with a character named Erika Berger. Blomkvist, the protagonist, and Erika were in a relationship when they were younger. When Erika got married to her husband, she tells him after some time has passed that while she loves him, she desires Blomkvist. Her husband is pretty much totally okay with her continuing her sexual relationship with Blomkvist, leaving them with an open marriage. On his end, Blomkvist still flirts and has sex with all kinds of women. (Granted, at least part of it might be because he spends a substantial amount of time away from Erika in the first novel. In the third, he starts a relationship while he's working in close quarters with Erika, and she seemingly begins to accept that he might soon have a real partner.)
 * In Sergey Lukyanenko's Night Watch, Anton is prophesied by Geser that he and Svetlana will have a powerful Other child. Both are attracted to each other but are apprehensive about the prophecy. During a Night Watch retreat, Anton catches her after she has a theesome with Ignat (an incubus) and another woman. The next morning, she realizes he knows but is mad that he doesn't seem to care. Anton actually tries to justify her actions, which causes her to blow up into a tirade on the stupid prophecy and the fact that she hasn't had sex in years (presumably, since her husband left her). This, of course, begs the question of why she would choose to have sex with another man and another woman rather than her boyfriend, for whom she has feelings. This is especially jarring because Ignat previously tries to seduce her (it's his specialty) but fails miserably. This incident is never mentioned again, and they end up getting married and having a powerful Other daughter.
 * In Cujo, Donna has an affair out of a desire to escape feeling old and bored. While her husband is obviously less than thrilled, they manage to work past it . Donna's lover, meanwhile, trashes her house when she breaks things off with him and manages to convince himself that he was heroic in doing so.
 * In Chosen, Zoey spends her time balancing her human boyfriend Heath, her vampire boyfriend Erik, and the twenty five-year-old teacher Loren Blake. Word of God is that it's not a good thing that Zoey hid her relationship with Blake from everyone (Erik does know about her being with Heath and is not happy about it), but there is the implication that Erik is a jerk for not being alright with Zoey having multiple boyfriends.
 * Discussed in How Not to Write A Novel. Among other things, they mention that having the protagonist cheat on their significant other first is a very good way to make the protagonist Unintentionally Unsympathetic.
 * Zigzagged in A Song of Ice and Fire. On the "good" hand, Eddard Stark is a protagonist and he and his wife Catelyn were "on a break" in the sense that he was away at war for more than a year; Catelyn acknowledges that he has needs and doesn't begrudge him finding comfort in some other arms. On the "bad" hand, Catelyn is ALSO a protagonist, and, even worse, when the affair bears fruit in the form of Jon Snow, Ned insists on raising the boy alongside his and Catelyn's own trueborn children, leaving her with a constant reminder that she is essentially his Second Love. Catelyn comes off as The Resenter, and no one thinks she was unjustified.

Live-Action TV

 * The Jonathan Creek episode 'Angel Hair' features an adulterous husband who, adultery aside, is depicted as an otherwise decent man who feels genuinely stifled in a marriage that, from his point of view, is lacking in passion. He's still treated as something of a hapless fool, though, especially considering that the wife he's cheating on is a beautiful pop singer who, whilst she's not quite the passionate sex goddess that the media depicts her as, is nonetheless a loving, caring woman who clearly thinks the world of him.
 * In another episode House of Monkeys a woman has an affair with her father-in-law. However, both she and her husband are portrayed as utter twits, and their story ends with their mother/mother-in-law shouting at them: "if only you would just take your marriage by the scruff of its neck and make it work!"
 * The pilot episode contains both kinds. The victim's affair is considered unsympathetic when it's with an oversexed French model. However it's later portrayed very sympathetically when it's revealed he was never having an affair with the model at all, but with his unglamorous housekeeper with a crazily jealous husband.
 * Blackpool features both. Ripley's affairs are casual sex, while Natalie's is about love.
 * M*A*S*H was pretty decent about men who cheat while away at war. Hunnicutt, and Potter's son-in-law felt intensely guilty for the act, and wanted to make things right. In both examples, the message was "You made a mistake; don't let it harm your wife; she doesn't need to know, but go back to her and love her like you never loved her before." All the more poignant with Hunnicut because it was Casanova Hawkeye who stepped in to save his friend's marriage.
 * That was the later seasons. In earlier seasons Trapper John, Henry, and Frank all have continuous, ongoing affairs and feel no remorse.
 * Goodnight Sweetheart. Gary Sparrow, the time traveling hero was in a relationship (and later marriage) with two different women in two different time periods (the 1940's and the 1990's). While the series treated the affair itself as wrong, Gary personally was always portrayed very sympathetically as a man impossibly caught between two women he loved and as feeling very guilty for doing so.
 * Used somewhat lightheartedly in Season II of Entourage. Unsure weather or not his girlfriend Kristin (of whom the rest of the boys don't approve) is cheating on him, Eric gets drunk and sleeps with a Perfect 10 model. He's guilt ridden for much of the remainder of the episode ... until Kristin confesses to him that she HAD been cheating on him (Ironically she justified it by doubting that E had been staying faithful in Vince's company). Eric then gleefully tells Kristin about the affair as he leaves.
 * Used on Friends, where Ross sleeps with another woman not only because Rachel says that they should put their relationship on hold take a break, but because he believes that she is sleeping with Mark. The episode after they split for real shows that while they don't necessarily agree with Ross, the other characters understand where he is coming from. Also used with Rachel herself. While she at first seemed to have the same mindset as the others, she ended up going the rest of the series run without admitting fault. Considering how "We were on a break" was one of the show's Running Gags, it wasn't as though she didn't have the opportunity to rethink her position.
 * Jericho has Eric Green, the protagonist's brother and aide to his Mayor-father, and all round swell guy. He's quickly shown to be cheating on his wife with the local Bar owner. Yet he is not portrayed as a soulless monster and when confronted points out how his marriage is basically winding down, and how he has genuine feelings for his new lady.
 * Will and Grace. When Will's father has an affair, he actually admits it being his own fault, though still decided that he wouldn't tell his wife. When it gets discovered that both of his parents are having affairs, they actually take an equal share in the blame
 * An interesting example is Rome. Servilia's anger over having been betrayed by Caesar is her driving force throughout the first season, and is one of the major reasons behind his untimely death. But Servilia isn't Caesar's wife, she is his mistress. And he didn't leave her to go back to wifey Calpurnia, he left her for his "real" lover, the Roman republic. Whether we are supposed to side with Servilia on this one or not is up for discussion.
 * House after he and his now-married ex-flame, Stacy, sleep together. Wilson tells her off for toying with House's feelings (of which she believes he has none) and Cuddy refuses to tell her that it would be fine for her to leave her husband.
 * Played with in an episode of New Tricks—the team are investigating the death of a wife who, having given up a potential musical career upon getting married, was feeling stifled in her marriage to her down-to-Earth, seemingly incompatible husband and ended up having an affair with a male gigolo; Sandra, who was the original investigating officer, feels a bond with the woman and suspects the husband of murdering her; the audience is initially encouraged to sympathise with her, and to suspect the husband. At the end, it's revealed that he didn't do it, but in fact knew that she was cheating on him, but was happy to let it continue because he knew that she didn't love him any more, but he still loved her and just wanted her to be happy. Seeing the man break down upon revealing this, the wife doesn't appear quite as sympathetic as she previously had, and her actions appear more selfish and cruel.
 * Used in Sex and the City where Carrie cheats on Aidan with Big, who happened to be married at the time. Aidan is not once portrayed as doing anything to "make her cheat", Carrie more that acknowledges that the affair was hurting everybody all around, and Big of all people is shown the one to be "wanting more out of life" due to his dissatisfaction with married life. "Everything we own is beige" is notes in lament. When Carrie admits the affair to her friends, she's actually hoping they'll tell her what an awful person she is. Aidan breaks up with her when she tells him, and though they later get back together the second break up (due to differing ideas about getting married) isn't portrayed as anyone's fault.
 * Noah's Arc: Wade cheating on Dre with Noah is "good adultery" that supports the One True Pairing, while just about any other form of adultery seen is of the "bad" variety.
 * The second episode of Castle has a particularly good example:
 * Another episode revealed that Castle's first wife Meredith, who is also the mother of his daughter, had an affair with a director and abandoned him and Alexis to move to Los Angeles to start an acting career. Castle seems to hold no particular ill-will against her, to the extent that he's willing to hook up with her again whenever she's in town.
 * Played with in Frasier, Frasier suspects that his father Martin had an affair whilst still married to his (now deceased) mother, and is shaken when Martin admits it. This affects his relationship with his father, Frasier being unable to forgive this betrayal, until he learns that Martin lied; it was actually Frasier's mother who had the affair. Martin blamed himself for it, and encouraged Frasier not to let it affect his feelings towards his mother, something which Frasier had little problem with. It should be noted that his brother Niles, however, had little trouble accepting it even when it seemed that Martin was the guilty party, reasoning that the two obviously managed to overcome it and have a happy marriage from that point on.
 * Frasier himself is a victim of adultery, his wife Lilith having had an affair in Cheers—he even comments on learning the truth that the shared experience of being cuckolds has given Frasier and Martin a rare something that they have in common. Lilith, for her part, is not well treated by the other characters, although her adultery is just one of the reasons why Frasier's family doesn't like her.
 * Niles and Maris also encounter this trope. In Niles' case, he is heavily attracted to Daphne throughout the series despite being married, but is portrayed sympathetically, while Maris' affair with their marriage counselor is depicted as selfish and the reason for Niles to initiate divorce proceedings. However, it's presented as obviously a lot more complicated than this; Niles ultimately never acted on his feelings for Daphne while he was married (although he was sorely tempted at times) and is willing to acknowledge that the Daphne situation could have nevertheless had a deleterious effect on his marriage whether he acted on them or not, while Maris' adultery is clearly shown as being the back-breaking straw on top of a large pile of selfish, unreasonable and unfair behaviour towards Niles.
 * Grey's Anatomy, as is appropriate to its name, plays the sympathy of adultery off of both ends. The first season cliffhanger involves Meredith abruptly discovering that her boyfriend Derek (better known as Doctor McDreamy) is actually married when his wife Addison flies in. The second season opener works under the assumption that he's done something horrible by getting involved with Meredith- until the very end, when a patient asks Addison how she can stand to be in the same room as Meredith when she slept with her husband. Addison is incredulous, and tells the patient that she cheated on Derek first and that was why he came to this hospital in the first place- to get away from her. She then sternly tells the patient that she owes Meredith an apology. As the season progresses, we also see that she holds Derek no ill will for the affair, and is perfectly willing to accept a divorce if he wants to continue seeing Meredith.
 * What makes this interesting is that it's clear from Addison's reaction that she thought Meredith and the other interns already knew all this- Addison knew there was gossip going around about her and she confronts some interns earlier in the episode. Apparently all the characters besides the doctors were Locked Out of the Loop.
 * Also interesting is the fact that Addison and Mark (the guy she cheated with) are presented as being as much the One True Pairing as Derek and Meredith (at least up until Addison left the show), and this, more than anything else, is the reason why they slept together. Derek was upset not because Addison cheated on him sexually, but because she fell in love with someone else.
 * Well, and the fact that Mark is his best friend. (Having said that, Mark is still a regular on the show, as opposed to following Addison to her spin-off, and everyone's more-or-less buried the hatchet.)
 * More straightforward later in the show. They're being subtle, but it's pretty clear that adultery is bad-flavored, with  as the wronged party.
 * Nip Tuck screws around with the concept of Good Adultery, Bad Adultery so much that's it's pretty impossible to find any sort of consistent standard. To wit-
 * Matt's girlfriend cheats on him with another cheerleader. This is treated as extremely bad. It is treated less bad however when he starts dating her girlfriend who has decided she isn't really a lesbian anyway (they met because Matt's lesbian girlfriend convinced him to join them in a threesome, as part of an abortive effort to salvage her relationship with the not-really-a-lesbian cheerleader).
 * There's a nuanced portrayal of Sean's affair with a patient, which Sean appears to have initiated on the suspicion that his wife was having an affair with a hunky student. She wasn't. What really screws things up, though, is that their staff psychologist Grace suspects the affair exists and confides her suspicions to Christian. He promptly takes this information to Sean, who is furious at her for discussing suspicions about his personal life and nearly fires her- before she reveals that Christian had sex with her and that unless they have a professional reason to fire her she can file an unlawful termination lawsuit. Christian is either oblivious to the fact that Grace was telling him this because he's Sean's best friend, not because she's a gossip, or he's a Jerkass who was trying to use this as an excuse to get rid of her.
 * It's treated as bad that Christian had sex with Sean's wife-to-be Julia right before she married Sean. However, Sean being royally pissed off when he finds about this betrayal is treated as an overreaction. Granted, all this happened over fifteen years ago. On the other hand . If this sounds contradictory with the entry below it's because the "betrayal" dynamic shifts entirely depending on whether Christian or Julia is doing the betraying.
 * For some reason it's worse that Julia cheated than it is that Christian did it with her, even though the latter is Sean's best friend and business partner. Christian is Easily Forgiven after a few episodes, but Sean isn't quite as nice to Julia. He verbally abuses and harasses her at every opportunity, invites his new porn star girlfriend to Matt's school functions, and tells Julia's mother to go screw herself when she tells Christian and Sean that Julia's about to head into an emotional breakdown and she needs an intervention..
 * In the third season Julia starts going out with the hunky student as a result of everything that happened above. This is the only particularly straightforward use of the trope's conventions.
 * As you might be able to guess, it's hard to tell whether they're trying to subvert the trope's conventions or just doing a really bad job of using it straight.
 * Law and Order Special Victims Unit has an unusually nuanced portrayal of this trope. When Elliot is separated from his wife, Kathy, he has an extramarital encounter but still mentally considers it cheating. After they've reconciled, one scene has Elliot's wife bringing up the question of whether they'd slept with anyone else while separated. Elliot admits that he had done so, but refuses to ask Kathy the same question, as he wants to put their marital troubles behind them.
 * An episode of Flashpoint deals with a husband and wife who had been trying for many times to have a baby and failing. The wife becomes increasingly obsessed with trying to get pregnant and having a baby and the husband becomes frustrated with her inability to talk or think of nothing else. Then the husband runs into an old friend and sleeps with her. Only to realize that what he did was wrong and afterwards genuinely loved his wife more.
 * In The Office (USA) a long time was spent having Angela engaged to Andy, but sleeping with Dwight, the one that she really loved at the time, though had left for Andy because Andy was "less of a risk." This example sits on both sides of the trope because Dwight and Andy are both shown to be sympathetic in that scenario, which ends with her losing both of them as viable romantic options.
 * In Tales from the Crypt, a housewife becomes bored because her scientist husband is too busy with his work to pay attention to her. Inspired by a soap opera, she strikes up a relationship with a repair man. In this case, the husband was shown as being more sympathetic, although with a good bit of Sanity Slippage and Disproportionate Retribution.
 * Deconstructed rather strangely in Merlin. Being a family show, the adultery between Guinevere and Lancelot takes place before her marriage to Arthur, consists of only a kiss in the dark, and happens whilst both Guinevere and Lancelot are under a spell. Oddly enough, this is still referred to as "adultery". The consequences are dire, as Arthur ends up banishing Gwen from Camelot. Even worse, nobody ever finds out that Gwen was under an enchantment at the time, and the season ends with Arthur taking her back because he still loves her - not only forgiving her for something she didn't even do, but offering no kind of apology for banishing her from her home on pain of death.
 * Between the Lines features an example of the protagonist committing bad adultery. Tony's womanising is frequently portrayed as a character flaw that.

Music
"Betty's been spending lots of time out late with Dr. Martin/ She says that they're working on the baby every night!/ And Dr. Martin sends her presents like new underwear and a bottle of wine/ I guess I'll keep writing checks until the day that baby is mine!"
 * Jonathan Coulton's song "Betty and Me" is about a man whose wife is cheating on him with a doctor under the excuse of making Designer Babies. The only thing that makes the song funny instead of disturbing is that the man's wife isn't even trying to hide her affair; the husband is just that oblivious. That being said, it's hilarious and is meant to be so.


 * Reba hits all sides of the scale:
 * She sings "Little Rock... think I'm gonna have to slip you off" because the marriage fires have dwindled. And also her cover of Ring On Her Finger, Time On Her Hands.
 * She also sings the haunting song One Promise Too Late about meeting her soul mate, but being too noble to drop her husband, who's been nothing less than good to her. "I'm not sorry that I met you... I can't have you, but I never will forget you. Where were you when I could have loved you? Where were you when I gave my heart away?" And also partially in The Heart Is A Lonely Hunter, where she turns down the married man with the ring on his finger.
 * And then there's When Whoever's In New England's Through With You (usually listed as Whoever's in New England), where she knows that her man is cheating on her, but is willing to wait out the affair. (In the music video, .)
 * Speaking of retribution, Garth Brooks' The Thunder Rolls has the wife of the philanderer kill her husband—or at least preparing to at the end ("Tonight will be the last night/She'll wonder where he's been!"), after waiting up late, fretful and worried for his life as he returns from a rendezvous.
 * Papa Loved Mama has the wife sleep around with various men on the town while her husband (a truck driver) is on the road because she can't stand being alone all the time. Husband comes home unexpectedly with a dozen roses and a bottle of wine looking to surprise her, finds out she's not there, and kills the wife by running his truck through the hotel she was cheating on him in. This song is one that puts both partners involved in a sympathetic light.
 * Another of Garth's singles features an "other woman" that isn't even an animal, much less a woman: Rodeo. ("Well, it ain't no woman, flesh and blood/It's that damned old rodeo")
 * Madvillain's "Fancy Clown", where Viktor Vaughn expresses the pain and frustration of being cheated on by your woman, especially when you know (and hate) the guy she did it with. How does he do this? By calling her, and telling her that it's over, oh, and he's been sleeping around behind her back, too, with several women including her own mother. He doesn't seem to grasp the hypocrisy at all, and it seemed like so straightforward at first, too; The opening features a mournful singer telling the story of how "I hear you in the background whenever I phone, telling your brother to say you're gone... You've been dipping around the town with some fancy clown." What makes it better is that she's cheating on him with MF DOOM A.K.A, Daniel Dumile A.K.A.,... Viktor Vaughn.
 * An Alternate Character Interpretation is that his assertion than he had sex with several other women during the relationship is a lie concocted in a pathetic attempt to hurt his (ex-) girlfriend.
 * Played with in the Eagles song "Lyin' Eyes"; the adulterous Gold Digger protagonist of the song is portrayed in a surprisingly sympathetic fashion, as a lonely woman trapped in a loveless marriage to an old man. The song still notes, however, that she did bring it on herself by marrying the guy solely for his money, and that her way of dealing isn't exactly laudable; she's betraying her husband and stringing along her boyfriend by promising that she'll leave her husband for him without any intention of doing so.
 * Long Black Veil originally recorded by Lefty Frizzell, later covered by Johnny Cash and the Dave Matthews Band among others. The song tells the story of a man wrongly accused of murder but refuses to provide an alibi that would exonerate him because it would mean revealing the truth that he was screwing his "best friend's wife" at the time. The protagonist ultimately takes the secret to his grave after being convicted and sentenced to death by hanging.
 * Nearly the exact same plot is used in Gary Moore's Over The Hills And Far Away, later covered by Nightwish. Instead of a murder it is a robbery, and the man spends ten years in prison instead of being executed.
 * In Pink Floyd's The Wall, Pink (a rockstar) invites groupies to his room but eventually starts to ignore them. He calls home to find that his wife has been cheating on him; a mental apparition of her tells Pink he "should have talked to [her] more often." This one is hard because Pink is portrayed simultaneously in both a sympathetic and a demonizing light.
 * The guy in Steely Dan's "Dirty Work" clearly understands the ambiguity of this sort of thing in reality. He's the guy having an affair with a married (or otherwise taken) woman while her man is "out of town": she's clearly looking for something she can't find with her husband (or whatever), but the man himself realizes exactly how despicable the whole situation is...and still does it anyway, for reasons he can't quite explain.

Newspaper Comics

 * For Better or For Worse uses the trope, giving us Anthony constantly pursuing his childhood sweetheart Elizabeth... while married to Therese. While Anthony is clearly meant to be the one we sympathize with, it didn't work too well for many readers.
 * An earlier example has Elizabeth at the other end, being cheated on by her long-term boyfriend at college. Intriguingly, when she finally figures out what's going on and confronts him at the other woman's apartment, the other woman immediately turns around and cries "you pig! You're cheating on me!?"

Video Games

 * This is whole point to the H-game Secret Wives Club. It is portrayed mostly sympathetically for the protagonist and the women involved, though both sides do acknowledge the implications of their actions and lampshade how unsympathetic it looks to another point of view.
 * Used in the old Sierra game Conquests of Camelot in which the player has to retrieve a veil from a prostitute on behalf of a husband so that he can prove to his wife that he didn't cheat on her. He gets away with it. This creates some Moral Dissonance considering the storyline is based on Lancelot and Guinevere's illicit love affair cursing the land, causing Arthur to go out in search of the Holy Grail in the first place.
 * One of the characters in Discworld Noir is an old lover of Lewton's who broke off the relationship unexpectedly and rapidly vanished. During the game she returns, and reveals that the reason for the sudden heartbreaking was that she'd actually been married the whole time, but up until she disappeared, she thought she'd never see her husband again; once she discovered this assessment to be false, she decided fidelity was the best option. The game doesn't really pass judgement one way or the other over the morality of the actual relationship between her and Lewton, but Lewton himself holds one hell of a grudge over how fast she left.
 * In Baldur's Gate 2, Keldorn's wife is unfaithful because Keldorn is Married to the Job and the period between each time she sees him is measured in months, if not years. If you confront the man she's seeing he's remarkably blasé about the whole affair, as he knows Keldorn's wife actually loves Keldorn and was only unfaithful because she was lonely and because Keldorn's daughters needed a father figure in Keldorn's absence, and it's further implied that there were certain... obstacles to physical intimacy between her and the other man. If you convince Keldorn to reconcile with his family and retire, the other man immediately backs off and the affair is resolved to everyone's satisfaction. Alternatively, you can bring the matter up to the courts, which will get the man hung, Keldorn's wife imprisoned, and Keldorn's daughters hating him forever to keep him in the party.
 * In Assassin's Creed II there are side missions called "beat-up missions". The player must locate cheating husbands and boyfriends and beat them senseless. Anvilicious enough for you? Making it a bit hypocritical, Ezio is a Casanova and proud of it, chasing after any woman who catches his fancy. However, the closest he gets to instigating an affair is seducing Caterina Sforza, who is a widow who never loved her husband to begin with (to the point of ordering his death).

Web Comics
"Durkon: And bein' a dwarf is about doin' yer duty, even if it makes ye miserable. ESPECIALLY if it makes ye miserable!"
 * Done in an early Order of the Stick story arc - while Durkon and Hilgya (of the Linear Guild) are off alone together, Hilgya tells the story of how she came to live in the human lands: she was forced into a marriage with an "oppressive" husband ("Would you like a foot massage, sweetie?"), so she fled after unsuccessfully trying to poison her husband ("Cursed dwarven save bonus against poisons!"). Subverted in that Durkon chastises her for it - even though her story didn't relate her husband's actual words.


 * In supplementary material for And Shine Heaven Now, Erin hinted that Arthur Hellsing was the result of an affair between Abraham van Hellsing and Mina (Murray) Harker. If true, they'll probably get a pass on the whole 'adultery' thing because...well, if Arthur doesn't exist, then neither does Integra.
 * Played With in Queen of Wands—from the reader's perspective it first seems like Brad was cheating on Angela with Wannabe Wiccan Girl, which naturally hurt Angela. However, it's later revealed that their relationship was polyamorous—Angela was just hurt to realize that WWG was "the 'real' girlfriend" instead of her.

Western Animation

 * On King of the Hill, Dale Gribble's wife has had an affair with Native American John Redcorn, resulting in a very obvious offspring. Dale remains completely oblivious to this fact, played for ironic laughs as he's usually a tinfoil-hat overly-suspicious conspiracy nut. The entire affair is based on Nancy's physical attraction to the hunky John Redcorn, and Dale is shown to be entirely faithful when given the chance to cheat and seems to be a good if somewhat eccentric husband. Also, when she starts to get back together with Dale once she realizes he's a good husband, she is shown to feel guilty for cheating on Dale and taking advantage of his trust, and Hank and all of his neighbors/friends know about the affair, but keep it a secret from Dale, who presumably would go batshit crazy on his wife and John Redcorn. Redcorn appreciates their discretion. Oddly enough, when Hank goes to Redcorn to tell him about an erotic dream he had about Nancy, the first thing Redcorn does is tell Dale about Hank's lust. It's also hinted that Dale does indeed know, but chooses to ignore it, since in one episode he calls out John Redcorn entering through the window, then tells him to start massaging his wife.
 * Then there's another episode where it turns out John Redcorn has another child who was conceived at the same time as his and Nancy's, the dramatic thrust of the story is keeping the children apart before their pre-pubescent UST has any squicky side-effects. Nancy is furious with John when she discovers he was cheating on her while she was having an affair with him. He also got mad at Nancy when he found her in bed after having sex with Dale (you heard that right) so after Dale bashes him on the head with a lamp (because he's you know breaking and entering) he then apologizes to John, because he didn't know it was him, and then helps him get back some of his tribe's land, and after Nancy decides to end the affair, Redcorn doesn't take it well and at one point bitterly demands why Nancy 'left him' for 'that' (i.e Dale). Hank bluntly points out that Nancy didn't leave Redcorn for 'that' -- she was with 'that' first, before she even knew Redcorn. Redcorn seems to get the point.
 * The trope also comes up as regards Bill's ex-wife, Lenore. In the past, She cheated on Bill and eventually divorced him, but Bill is portrayed as a victim who tried to be a good husband, while Lenore is portrayed as a cruel, manipulative bitch, who is largely responsible for Bill's life being as pathetic as it is.
 * On The Simpsons, the wear and tear of raising eight children erodes Apu and Manjula's marriage to the point where Manjula won't let her husband so much as touch her. A desperate Apu is courted by a fetching Squishee delivery girl, and after the ensuing affair, Manjula pressures Apu to go to ridiculous lengths (as in, eating a light bulb) to restore the same cold, lifeless relationship that drove him to another woman in the first place. The fact that the two of them were an Arranged Marriage is implied to have been a factor.
 * There was also an episode where Bart and Milhouse make it look like Marge is having an affair with Kirk. However, when Homer confronts Marge on it, Marge throws Homer out of the house, because he continued to press in spite of her repeated denials.
 * In Family Guy, at least when it came to Loretta and Cleveland. Loretta had an affair, and though it was Played for Laughs, it was fairly even-handed as she had a reason (she felt Cleveland lacked any passion), but wasn't seen as very much in the right, especially when we see her again in a later episode. Even later, Loretta shows remorse for leaving Cleveland... then accuses Quagmire of ruining the marriage.
 * Also from Family Guy, the time Lois cheated on Peter with Bill Clinton. Peter is clearly portrayed as the victim. Of course, Peter then goes and cheats on Lois... with Bill Clinton, since Clinton is just that persuasive (Peter: "Boy, you are good. You are REALLY good."), and neither Peter nor Lois would have done it under normal circumstances. This is also the same episode where Peter was given a pass to sleep with Lois's mother to even things out, but couldn't go through with it because he does genuinely love Lois.
 * In the season eight episode "Go Stewie Go" Lois cheats on Peter after she gets tired of his constant insults towards her advancing age. She then seduces Meg's new (normal) boyfriend. While making out with him on the couch, Meg catches the two going at it. Eventually, Lois tells Peter about her affair. Cut to Peter telling her why he was making such a big deal about her age (because he himself was insecure about his weight). Lois then makes up with Peter. Their next door neighbor Bonnie's former cheating nature is also revealed.
 * Another episode has Bonnie go to France with Lois with the express intent of having an affair, saying that the passion has gone out of their marriage. Lois is aghast, saying that Joe is a wonderful man and cheating on him will hurt everyone involved. Bonnie remains adamant about the affair up until the end of the episode, where Lois uses outright deception to convince Bonnie to stay faithful.
 * Played with on Moral Orel, in which both Clay and Bloberta are unfaithful, but neither is show at all sympathetically, because they're shown to be at the root of their own unhappiness.
 * In an episode of American Dad!, Stan finds out his wife had tons of boyfriends before meeting him, so Francine gives him a temporary divorce to have as much sex as he wants with whomever he wants. She changes her mind, of course, and begs him to come back after seeing him on a date. He refuses, citing their original deal. He then comes back to her, and she is overjoyed that he didn't go through with the "affair". Stan cheerfully replies that he actually married the other woman and had lots of sex before divorcing her (apparently, in one day), shocking Francine.
 * Another episode has nearly all women in town revealed to be members of the Ladybugs, a club for women who cheat on their husbands. They do this as a status symbol and for shopping perks (i.e. no good reason). Francine accidentally becomes a member after the women catch her in a Not What It Looks Like situation with another man. Apparently, all the husbands are clueless, while their wives believe that being a slut is a good thing.

Real Life

 * The Gosselin family, of Jon and Kate Plus Eight fame, sort of zig-zag around this - while Kate was originally blamed for making Jon miserable enough to seek happiness with another woman, she's recently began gaining more sympathy after Jon allegedly proposed to his new younger girlfriend.
 * Part of this came from the media; Jon was proposed as the villian in the relationship, being weaker emotionally, while Kate was built up as the strong mother trying hold it together for her children. Rare was any story on them were her emotional abuse came into the center, instead it was all about how Jon cheated. When stories of her cheating came into play, it almost never was her fault for doing so, or as evil as Jon's betrayal.
 * Spencer Tracy and Katharine Hepburn are even today regarded as not only the good kind of adulterers but one of the most enduring stories of Hollywood romance, despite Tracy having been married (and technically estranged since wouldn't divorce her because he was a devout Catholic) to actress and fundraiser Louise Treadwell over the entire course of their relationship. The two never spoke publicly about their relationship, never appeared in public together when there wasn't a publicity reason for it, and Hepburn neither attended Tracy's funeral nor even spoke acknowledged their relationship until Treadwell had passed on.
 * Funnily enough, Tracy danced into Bad Adultery territory during his affairs with actresses who weren't Hepburn.
 * Ayn Rand drew a distinction between good and bad adultery. She had an affair with a prominent player in her Objectivist movement, Nathaniel Branden, a married man, and rationalized it by saying two people of their intellectual caliber were morally obligated to enter a relationship. However, Branden later had an affair with another woman, for which he was practically excommunicated from the Objectivist cause.
 * When news of Prince Charles' affair with Camilla Bowles (now his wife) came out, there was a media frenzy over the gall the man had - compared to his wife, Diana, who had had a number of affairs behind his back as well. Then again he did cheat first....
 * During Cromwell's era, adultery was considered a capital crime in much of Britain. This trope is illustrated by the fact that, while the legal system condemned it all as Bad Adultery, the populace at large acknowledged that Good Adultery was possible and subverted this law via jury nullification.