Give him space. Not always easy I know but if you are too clingy, too needy, too demanding it will turn him off. If you want to be with him that bad you have to play the game sweetie. Enjoying the time you are together, when you are not together get out and do your own thing: go out with friends, sign up for a class in something you enjoy, in other words make it evident that you are not sitting around waiting on him, that you have a life. If you are self-confident, not always available every time he does call (even though you want to be) and not hounding him about
"why didn't you call me, etc" I can almost guarantee more attention will come your way. You must think like a man, while behaving like a lady.....see?
Give it a try and lets see what shakes out........................