Do you have a good support system? Some friends who can perhaps distract you at the moment? It is hard to think what could have been or what should have. You both have been hurt by each other. Try to find a old hobby you used to enjoy doing.
And it seems my comment didn't send. I said try to be kind to yourself and allow yourself to mourn the relationship but always remember there are 7 billion people in this world. Ones bound to be right for you so don't become two hung up on one.
Someone who has been such a big part of your life will be hard to get over of course! Might sound a little morbid but I've sometimes looked at these things like a death. There is a certain mourning period you need to allow yourself. The key is not to rush and not to force it because if you push those feelings down they will only sit and mold until their smell draws your attention to them once again. Let yourself be angry, hurt, sad and you should almost become tired of it after a while and move on. Do try to minimize the time you spend stalking his facebook/twitter/myspace/IDK. Be kind to yourself and remember; there's 7 million people in this world, ones bound to be right for you.
I don't want to be with anyone till I get back on track. There's one guy I could be more close with, but I don't want to. When we started chat and meet more often, I couldn't stop to compare him with my ex. Soo I think I'll forget dating other guys for awhile. The things is that I lost all passion in life, I don't want to do anything usefull or creative as before. I'm school leaver this year but I don't know what to do in my life yet. And seeing him, so happy and doing things he likes makes me feel more miserable.
Ah as they say 'love is fire, but whether it's going to warm or burn your heart, you can never tell'. I know how you feel, maybe you weren't ready to leave him after all? maybe you broke up too soon, thought that some distance would make you miss each other. I don't know him at all so I can only speculate, maybe his relationship isn't serious? maybe he brought a girl to make you jealous, see your reaction? or he truly did move on quickly. It is like that dear, like they say 'it takes two to tango', in love as well, both must feel the same, otherwise one gives more than the other. I know it's very hard to let go, but honestly the best thing to do, is simply erase him from your mind, stop thinking about him, clean your mind, live as if you never knew him, and if someone else appears, take the chance Otherwise, if you find it impossible to get over him, tell him how you feel and try to work things out. Love is very hard and takes a lot of time.. you are going to need much patience. Unless he tries, shows in some way that he is interested in you and wants to give you another chance, there is no point in feeling crap about him. You deserve better.
This is probably going to be the hardest part about breaking up because even I don't know how to get over the whole "he doesn't talk to me anymore" part. I knew mine for five years, and now despite we're in the same college and by virtue of us being in the same major he sees me a lot, he just treats me as though I'm a stranger. The only way I've learnt to deal with it is to get new friends and try to put that part of my life in the past. I'm not really sure the pain will ever go away (It's been 4 months on my end), but at least making a new circle helps you feel like you're not the one at fault.
If you broke up with him, then remember at the time you did you probably did so for a very good reason. The problem comes from when the good memories begin to eclipse the latter bad ones, but just remember that the bad is more recent and it's what's more important. Yes, it's going to be hard, but the best way is to find something that helps you forget. Even if it's silly, as long as it helps you feel like you again.