I'm not saying give up, I'm just saying that your well being seems to be blocked by the thought of you getting back together.
Look at it this way.. it's a good to want that, but you have to be friends first right? How long will it take to become friends again? Beyond that is where the possibility of anything more lies. You need to be OK with that, because that is the cold hard truth.
Something that has kept me in check (albeit not as much as I'd like!!) is to think of what she has done to me.
This has changed my perspective.. maybe I don't want her back. I know I don't want the person she is now. Helps me look at her and say "she's still the alien.. don't want that"
Another thing... if you have time and need something to do, read up on other folks situations. You will be absolutely amazed at how many people are in the exact same boat you are. You could probably learn a ton just by interacting with them. I'm sure you could teach them as well.
Keep it up man.. you're doing good for what you've been through!!
