I don't think there's any one way to really get over someone. I've been in love with someone for a long time now, and he keeps getting more keen, to the stage where we're in a relationship in all but name, and then back to being best friends but definitely nothing more. It's an impossible situation, that can never end up in both of us being in a long term relationship, but I haven't been able to move on (this has been going on for months now).
I tried cutting all contact for a while, but I'd made this friend into my rock, so I couldnt back away completely. I'm so glad I have them in my life so that I can't get rid of them completely, but I don't know how much longer I'm going to be able to keep loving him without being allowed to.
I think cutting all contact is the best way to get over someone, in any situation. Is there any way you can stop seeing him completely? Another thing to try to do is to find someone else to think about. I found that when I was obsessiong about this boy, it helped me that I found someone else that I quite liked. They were never going to be anyone like 'the' boy, and they weren't going to be a serious boyfriend, but it helped me to have something else to occupy my thoughts. Otherwise just try to find other things to do to keep your mind off him - a hobby, or seeing other friends. I find writing helps me too, writing a diary of how I'm feeling and what I'm going through, and what I want to happen in my life. It something makes things more concrete when you see it written down that you want to move on, and forget about him, and so on. Worth a try, anyway...