Be the best YOU you can be. Invest in yourself. You are likely spent emotionally, financially, physically, and any other way in your efforts to detatch from you ex.
Take courses, read books, get in shape, join support groups, have a fling, fry bacon in the nude, play nicky-nocky-nine-door, post your ex's contact info on pervy porn groups,.... whatever to get on with your life.
Your ex is probably not worrying about you. Stop worring about him/her.
You will be with you for the rest of your life. Time to take care of you and build for your future. Learn the meaning of acceptance... here is a link about acceptance that has been very helpful to me... http://anonpress.org/FAQ/files/read.asp?fID=32
Get over it! Find a way. It is not easy but it is fabulous from this side! Yeeeee-haaaaaa!
Learn about yourself and your self-defeating ways. We all have them in some measure and it is a life-long pursuit to bring them to the surface and deal with them. But as we grow we gain freedom. YES FREEDOM! Freedom from the hurt "they" once caused us.
My word of wisdom is look forward, not back. You are worth it and there is a ton of life to live!