Brian Jackson is an *beep* disliked the character so much

He offends Alice's parents that night and is thrown out the next morning. So he goes on a date with Rebecca(another completely irritating character) and goes on to shag her only that doesn't happen.

Then this same guy screams and smashes things when he finds out Alice has slept with Spencer and also misbehaves with her the next morning as if she were the bad girl , the untrustworthy cheater. The entire film actually tries to portray her as such where Brian is the real D'Bag.

Alice even tries to "explain" things to him.
But my question is , what for? They did not commit to each other. A candlelit dinner and a failed attempt at new-year-eve sex do not spell commitment.Alice doesn't owe him anything. And more importantly , he is no less of a cheater than she is.So nothing gives him the right to get mad at her.

Or may be, it's because he is a sexist pig.And as for his new love Rebecca,she doesn't appear to be the commitment type of girl either , does she?