4thTime I think there's a difference between the "generic" girl who falls for bad guys, and the way your girlfriend reacts.
Concerning the 1st case. First, it is my cynical belief that out of any given group of human beings, 90% are complete idiots. This includes our female population, so don't worry about them. You will never understand them, and you don't want anything to do with them.
Concerning the 2nd case (more seriously): Most people seek security in a relationship, and when they get too much, they start going off on adventures. It's as if we want to be loved, and despised at the same time. Most people can't deal with total safety in a relationship: "You can feel *too* secure". So I don't think your girlfriend actually gets a kick out of you treating her badly, but rather that she notices superficially something she knew subconsciously all along: That you are her "special person", and that your love and well-doings are not to be taken for granted.
P.S. I just noticed Nikki's signature. Seems like evidence for my theory, right?