Off-Screen Breakup

Last time we saw Alice and Bob, they were dating. Things seemed to be going fine, and they're happily in love. Now we see Bob flirting with Carol. Someone brings up the fact that he was dating Alice, and Bob will respond with "We broke up", or "Things didn't work out".

This is more than a little jarring because it is just freeing up Bob to be in a new relationship (or to be single), without actually showing how the last one ended.

Compare to Downtime Downgrade

Anime

 * In Mobile Suit Gundam SEED, Dearka Elsman and Miriallia Haww seem to be headed vaguely in the direction of becoming a couple, and apparently do so following the end of the series - only to have broken up before the beginning of sequel series Gundam SEED Destiny.
 * Ditto for Amuro and Sayla in the end of the original series and the beginning of Zeta.
 * Pokémon: Might not fit because we never saw Brock and Professor Ivy dating, but we never really find out what happened between the two.
 * The Devil May Cry anime stated that Dante and Trish, after the first game events, didn't only became a couple: they ever got married, but they broke up before the series start.
 * Bulma and Yamcha broke up between the Frieza and Cell Sagas in Dragon Ball Z, clearing the road for Bulma's relationship with Vegeta.

Fanworks

 * Often done in Fan Fiction with the Official Couple when the fanwriter wants to write about the Fan-Preferred Couple without the pesky task of actually having to write the breakup. Considering the alternatives, this method really isn't all that bad.

Film

 * This exact same thing happens with the direct to video An American Tail movies. Tony Toponi had his Love At First Sight moment with Bridget in the first movie and they seemed like soul mates. Come the third movie, not only is the second movie now All Just a Dream but Bridget is gone for some reason and Tony is flirting with someone else.
 * In the Die Hard series, John McClane makes up with ex-wife Holly in the first two films, but he's single again at the start of the third.
 * Streets of Fire: Tom Cody and Ellen Aim do this when Tom leaves town for some sort of war for 2 years.
 * Indiana Jones: Indy and Marion between Raiders of the Lost Ark and The Last Crusade.
 * The Librarian: Flynn breaks with Nicole at some point after the first movie, before the second one...
 * Men in Black. Linda Fiorentino is (kinda) Will Smith's love interest; come the next movie, she's outta there! (Because she apparently wanted to go back to normal life...)
 * Ben and Abigail between the two National Treasure movies.
 * Pocahontas and John Smith between the two Disney Pocahontas movies.
 * Professor Klump does get the girl in Eddie Murphy's version of The Nutty Professor. He's lost her again by the beginning of its sequel. We can guess why it happened this time, but the implied reason itself is a Shocking Swerve.
 * James Bond. All part of the formula.
 * Subverted in the Austin Powers series, where Austin and love interest Vanessa get married in the first movie. At the beginning of the second movie, Vanessa is revealed to be, thus making room for Felicity Shagwell.
 * The Karate Kid Part II used this to explain the disappearance of the first film's love interest character.
 * In Transformers Dark of the Moon, Sam's previous girlfriend from the first two films, Mikaela Banes is given a simple mention early on, that she broke up with Sam at some point between the second and third film.

Live Action TV

 * Leonard's girlfriend in The Big Bang Theory.
 * Also, Bernadette and Howard.
 * The second season of Da Capo subverts this: The protagonist of the first season is constantly minded by his haremettes and there are hints that his first season love interest either broke up with him or died....
 * NCIS: We get hints that Abby and McGee's relationship is in trouble during early seasons, but we never get to see them actually break up.
 * Fourth season of Dexter:
 * And again in the sixth season when.
 * Andy and Erin in The Office.
 * Power Rangers: the break-up by letter for Tommy/Kimberly. Shippers for that fandom still have trouble accepting that one.
 * Omar and Dante from The Wire end season three still together, but with a noticable strain on their relationship, and at the beginning of season four, Omar is already living with someone else (Renaldo).
 * Smash and Waverly, and Lyla and the Christian guy she was dating, on Friday Night Lights. Actually, a lot of the relationships on this show, because they don't show too many episodes that take place when football season isn't going on.
 * Puck and Quinn in Glee.
 * And Santana and Sam sometime after.
 * In Community episode Basic Genealogy Jeff and Prof. Slater. When we last saw them together, their relationship was doing okay, but they break up before the opening credits. Word of God, this development occurred to have Jeff get together with the Guest Star of the week.
 * Ashes to Ashes: Chris and Shaz between seasons two and three.

Video Game

 * Guybrush and Elaine during the Time Skip between The Secret of Monkey Island and Monkey Island 2: LeChuck's Revenge.
 * And then they mysteriously are back to being in love at the start of the third game...
 * Snake and Meryl between the first and second Metal Gear Solid.

Web Comic

 * Dominic Deegan: Hansi.
 * In Something Positive, Davan and that girl who liked to strangle him, though in that case it was explicitly a non-romantic relationship just for sex.

Web Original

 * In Survival of the Fittest, Jonathan Jarocki and Anna Chase broke up before they got on the bus, as revealed in Anna's opening post, mainly due to the fact that the pairing was almost unanomously hated among the writers.

Western Animation
""What happened to your self-respect?" "I lost it in the second divorce settlement.""
 * Jay being single in the Webisodes following The Critic Season 2 was explained with one of the first lines:


 * King of the Hill had a season finale where Khan's mother moved in with him and began dating Bill. At the start of the next season she was gone and Bill had gone back to his losery loneliness.
 * In the second season premiere of Young Justice, broke up during the five year Time Skip.