i agree go out and have fun, i know exactly how you feel... but if you sit around waiting it will never happen, if you get out there and find someone great! if the girl you like finds out and realises what she is missing even better! this is not suggesting you should use someone to get to her, but one thing is for sure, sitting around feeling sorry for yourself and running over every moment of contact in your head will NOT win her over.... forget the regret, get on with life, and have fun, its just another step taken on the journey of life my friend.

good luck!!!!