Close Iryan, but no cigar. :x
Ah, found it. It's kinda like
this sort of stuff. (Warning, TVTropes link). More generally, it's situations where someone is being pinned for something they didn't do, or a misunderstanding leading people to think and act on an assumption that's actually false. That drives me mad. >_<
You see it a lot in love-related dramas too, where Person A pushes Person B into an incriminating position unwillingly, Person C walks in who is Person B's lover, sees them and thinks Person B is a lying scumbag when really they aren't. That sort of thing. Ughhhhh.