Derailing Love Interests/Playing With

Basic Trope: A character who was previously depicted as a good person suddenly starts to become abusive just so their lover can be with another character.
 * Straight: Jack, Jill and June are in a Love Triangle, June at first seems to be good friends with Jack and Jill and both Jill and June seem to have equal chances with Jack. However all of a sudden, in a fit of rage, June attacks Jill, losing everyone's sympathy. Jack marries Jill soon afterwards.
 * Exaggerated: Jill and June seem like the best of friends but one day June snaps out of jealousy, almost killing Jack, and is promptly sent to jail. Jill is sitting by Jack's bedside when he wakes up.
 * Downplayed: Jack starts to notice little things like June being rude to waiters and disliking children, and realises she's not the angel he'd imagined her to be. (NB: if too downplayed, may verge on Minor Flaw Major Breakup)
 * Justified: June was a Bitch in Sheep's Clothing, acting like a pleasant person in public, and Jack doesn't notice her nastier tendencies until they're living together. Meanwhile, Jill's past sins are revealed to be All A Huge Misunderstanding.
 * Inverted: Jack starts being horrible to June the moment they start dating, and she dumps him -- let Jill have the psycho.
 * Subverted: June has a Kick the Dog scene, but she quickly sees the error of her ways and is forgiven for her actions.
 * Double Subverted: Jack forgave her for Kicking The Dog, but soon afterwards June forgets to use a coaster and Jack runs straight into Jill's arms.
 * Parodied:
 * Jack realises that Jill is his One True Love, but bewails the fact that he's committed to June now, and it can never be! The next moment, June runs in with a bloody knife in her hand, ranting that those nuns deserved everything they got. Jack: "Screw This, I'm Outta Here".
 * The whole episode turns out to be Jack reading a Die for Our Ship fanfic about a suspiciously familiar Show Within a Show. It ends on his shaking his head and muttering about "crazy fangirls..."
 * Deconstructed: June isn't blind; she can clearly see that despite claiming to have forgotten all about her, Jack is still pining over Jill. What's more, he refuses to admit it when she points it out. While Jack's friends talk about her being a Clingy Jealous Girl, the audience can see her side; Jack's obviously trying to have his cake and eat it too. When her frustration causes her to do something crazy, Jack uses this an an excuse to dump her and go to Jill (assuming she wants him back after he rejected her), telling everyone the horror stories about his Psycho Ex Girlfriend.
 * Reconstructed: June has believable reasons for acting the way she does, but she still comes across as oversensitive, jealous and self-centred, and not really caring so much about Jack as she does about her own image. Jack and Jill are undeniably the OTP.
 * Zig Zagged: Jack, Jill and June have been in several stories, sometimes Jack becomes an example, sometimes June becomes an example and sometimes Jill becomes an example so basically their relationships are a severe case of Depending On the Writer.
 * Averted: All 3 characters in the Love Triangle are consistently depicted as good people simply trying to find a relationship that makes them happy.
 * Enforced:
 * The reaction of Word of God seems to be "WHAT?! But Jack X June is the Official Couple! People prefer Jill to be with Jack?! HOW DARE THEY! I'll turn Jill into a Complete Monster just to show them!
 * In Fan Works basically any given Die for Our Ship story.
 * Lampshaded: Oh sure June NOW you decide to be so abusive?! I mean you couldn't pick a worse time!
 * Invoked: Jill tries to manipulate June into acting jealous just so she would look bad.
 * Defied: June is extra nice to new hubby Jack; "I worked so hard to win him over, I wouldn't want to drive him away while he's still got feelings for Jill."
 * Discussed: "Watch out Jack, now you put a ring on her finger you're going to see what she's really like."
 * Conversed: "You know, if June hadn't gone psycho I don't think Jack would have had the balls to break it off with her. Kind of like Archie with Betty and Veronica."

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