Most Helpful Guy
The reason does not matter. the only thing that matters is that he is a douche. Dump him now. right away. Lots of guys out there for you that will treat you well.
Most Helpful Girl
if he acts like that around his friends, then it's not an act. if y'all are having sex, then that could be the reason he's dating you. just to get some. if he really cared about you and thought you were sexy and all that, then he would show you off to his friends! every chance he got. and if he's denying you as a girlfriend, then that's even more reason to believe that he just wants someone to hook up with. tell him how you feel and ask him why he does those things. I'm sure you're an azming girl. tell him if he doesn't step it up, then you'll be out the door!