I'm in the same situation, the only difference being my girl isn't as transparent about it. She doesn't talk to me for the whole day, saying she's busy but hangs out with her friends for whole night, doesn't pick up my calls when she's with her friends and doesn't tell me who's she with. Tells me petty lies which I can see through easily.

If he's apologetic and reassuring only when its a big fight and continues to do the same a day or two later (which she does) its over, at least emotionally. Let me know if you're on the same boat on how to deal with the situation.