ok, I have read your live journal...and I feel very sorry for you, I can understand how you feel...but you must believe in yourself, YOU ARE JUSTTHE ONE FOR YOURSELF, and you must respect yourself...you are the only one person who can help you...so, try to sit and think...try to remember all evel thigs she did to you, write them down, it might help you to start realise that this girl is not for you...
then, try to get some social life, even if you dont want, force yourself to talk to people, go out, dont be stucked in her...as soon as you start thinking about her, just take a book to read, or watch TV, or start playing some strategy game, that will help to concentrate on smth else...
then, get rid of all things that can remind you about her, just everyth possible, all sweet cards, pictures, presents, TOTALY EVERTYHING...so like this you will have less possibilities that smth else will remind you about her....
and, if you can, it would be good for you to talk to psychologist...I think you could get a real help!!!!
Cheer up!!!!! EVERYTHING WILL BE GREAT IN A WHILE!!! life is always is like that black and white...you just need to keep yourself strong when it is black!!!
p.s. and it would be also better if yuo would stop communicating wiht your ex, coz it is obvious that she hurts you...stop going to the nightclubs where you can meet her..etc. You know this days that you are thinking about her just dont worth it, I mean it doesnt worth it to spend ur time on someone who dosent care about you....Good luck!