What could be the reason behind his rude behaviour?

oth r in their thirties.He was attracted to her very much sexually and tried his level best to get her but she was always very polite and declined him but they agreed to be friends.But the friendship went on only for a month and in between over a very silly issue he stopped talking to her.When she texted he replied back they r still friends but never called back.Now after a month he tries to avoid her..and sometimes deliberately comes in front of her and turns the other way...It is possible that he has a gf but she never had any problems with that he knows it-but y is he behaving like this with the woman he liked once? Is he hoping to change her mind?He knows that she cares for him a lot as a friend