Break Up Demand

Occasionally you get a character who doesn't hold with the usual methods of getting a couple to break up - you know, Twisting the Words, saying that they'll give their blessing when such-and-such a demand is met then Moving the Goalposts, spreading rumours and other Manipulative Bastard tactics...they just go straight to one half of the couple and order them to split up with their partner.

Well, at least their straightforwardness is refreshing...right? Well, not usually—they're not completely devoid of Manipulative Bastard traits. For a start, the partner they talk to is often not the one they know personally. So a father will order his daughter's boyfriend to break up with her, or a sister will demand that her brother's girlfriend ditches him. This usually signals that their intentions aren't entirely altruistic: if they made the same demand of the person they knew, that person would probably work out what they were up to and tell them to shove it. So they pick on the partner, who assumes that this "friend" or family member knows their lover better than they do. Normally, the interloper is trying to guilt the partner into pulling a Break His Heart to Save Him stunt.

At best, the character making the demand is a misguided Knight Templar - they honestly think the break up is the only solution to a perceived problem. In the middle are characters who are deluding themselves: they tell themselves that the break up is for the greater good, and try to ignore their actual, more selfish motive for doing it (for example, they want to date one half of the couple). And then you have the outright Manipulative Bastard, who knows he's doing this for selfish reasons, but wants to shift the blame for the heartbreak onto the person forced into doing the dumping.

This may also apply to close friendships rather than romances, especially in shows featuring younger characters,

Knight Templar characters are extremely prone to making a Break Up Demand, as is the Overprotective Dad. If the partner proves resistant to the demand, blackmail, or a verbal / physical attack with a degree of Why Did You Make Me Hit You?, may be used by the person interfering.

Anime & Manga

 * Tohma orders Shuichi to break up with his partner, Yuki, in Gravitation, on the grounds that Shuichi is bad for Yuki's health. Needless to say, Tohma is not a doctor, and is possibly more to blame for Yuki's "fragility" than Shuichi is.
 * Outright Blackmail version in Gakuen Alice—Natsume is ordered to cease his association with Mikan. Or else.
 * An overtly violent demand is made in the manga Mars - Hitomi is ready to crush Kira's fingers if she doesn't break up with Rei.
 * A favourite tactic of Akito in Fruits Basket, who hates anyone getting too close to the Zodiac Sohmas. Be warned if you associate with any member of the Zodiac: if Akito can't browbeat the Sohma into breaking off the relationship, that's not a problem—the God of the Zodiac will simply scream at and abuse you instead. And make you think that you are entirely to blame for all the misery that ensues. Just ask Kana.
 * Wolfram's uncle tries to pressure him into dumping accidental-fiance Yuri in Kyo Kara Maoh!, in order to secure the throne for Wolfram. Wolfram, however, schemes to ensure the best outsome for Yuri...
 * In Mens Love, Daigo's father sends his henchmen to get Kaoru to break up with Daigo, offering him a blank cheque, threatening to expose his sexual orientation at work, and telling him Daigo is getting married. Kaoru refuses and decides to take things into his own hands instead.

Comics

 * Archie Comics: In the "Betty future" of The Married Life continuity, Mr. Lodge orders Archie to break up with Betty, after the wedding has already taken place! This is supposedly just to make Veronica happy (though Mr. Lodge does promise to pay off Betty), but is actually part of a deeper scheme.

Fanfiction

 * There are possibly far too many examples to list in Fanfiction, but suffice to say the trope is endemic. It's a handy trope if the writer wants to write about the drama of a break-up, but doesn't want one of their OTP to be the "bad guy."

Film

 * In the backstory of John Sayles's Lone Star, the hero and his childhood sweetheart were forced to break up by the hero's father, a corrupt sheriff. They chalk it up to racism—she's Hispanic and he's white.

Literature

 * Referenced in Confessions of Georgia Nicolson. Jas claims that Georgia told her to break up with her boyfriend, Tom (making this a rare case where the "demand" was made to the actual friend, not the partner). Georgia didn't actually do this—Jas badgered her for advice, and Georgia (not renowned for giving sensible advice), commented on Jas and Tom's differing interests, and asked if Jas wanted to play second fiddle to Tom's eco-warrioring.
 * In Stefanie Pintoff's A Curtain Falls, Alistair Sinclair discusses the Broadway star Maud Adams (an acquaintance of his) and the control theatre magnate Charles Frohman had over her. Alistair says to his partner Detective Simon Ziele, "I do know his influence once led her to cut off a romance that he believed to be inappropriate." Ziele's narration suggests the romance was with Alistair Sinclair himself.
 * The Sharing Knife: Legacy - Dag's mother and brother demand his marriage to Fawn be invalidated. Dag's brother Dar mainly wants the arguing to stop, Dag's mother has more complicated reasons.

Live Action Television

 * In the tenth season of Friends, Ross is asked to break up with Charlie by Charlie's old boyfriend in return for a very important research grant. In the end, Ross loses Charlie (because extortion is so romantic), and we never learn if he got the grant.
 * There's an episode of Sex and the City where Samantha is going out with a man whose sister tells her that she's not comfortable with her brother seeing a white woman. Eventually Samantha breaks up with him for not standing up to his sister.
 * In Season Three of Buffy the Vampire Slayer, Buffy's mother, Joyce, demands that Angel stop seeing Buffy because of his curse and the likely outcome of their Mayfly-December Romance. By the end of the season, Angel has come to agree with Joyce...just in time to go off to his own self-titled Spin Off.
 * In Merlin, Arthur got this from Uther in the third season...Morgana found out they were going on a picnic and led Uther right to it, leading to Uther wanting to banish Gwen because she wasn't royalty. It took a big turn from there with the whole framed for enchantment thing, but it still counts.
 * In the CSI: NY episode, Blood,Sweat and Tears, the couple are from two rival circus families, and they make a suicide pact after their families tell them to break up. But then only the guy went through with it and later the body was dumped.

Video Games

 * In The Sims 2, your own Sims could demand that another sim "Fight" with their sweetie if they had enough Influence points, often doing enough damage to lead to a breakup.