let me tell you. ive been there, done that. With my ex, after we broke up (i broke up with him), we still fooled around (except i wouldnt let him kiss me because thats more personal to me than the rest of the stuff). He was there to fool around because he wanted me back and stupid me, let him have it. I never planned to get back together with him, so when he realized that that was never going to happen, we had a huge fight and havent talked since. So if you guys are doing all that relationship stuff because it makes you feel like you two are still together, DON'T DO IT.
Also, my current boyfriend is going thru what you are going thru. I'm confused about how I feel about him (i think you read my post - thanks for ur advice ) and we're on a break now. He called me yesterday morning (which he wasnt supposed to do because we're on a break) telling me how hard it is to not be with me and whatnot. I think you need to try to get your mind off of it and go out and do other things with other friends and just distract yourself. It's hard for me to say, since I'm on the other side, but your ex needs to figure out what he wants and if that means that you can't talk to him or see him, then so be it. Because you can't figure out how you really feel until you distance yourself from the problem, take in the whole big picture, and reflect on how you feel and sort out how you feel. Thats what you need to do and what he needs to do. So let him have his time to think. It's good that you gave it to him.
And remember, if something is meant to be, it will come back to you. Good luck.