I hope you're able to attend Alanon meetings. We are all human, we all make mistakes, and in relationships we get cranky. If you haven't seen your man in two weeks, it's ok to be bummed out. If he is that responsible, that together, he should be able to talk with you as an adult about the relationship.
Announcing your relationship is over via MySpace is very high school, very immature, and not very compassionate. It's not your fault, he just wasn't ready to deal with a normal relationship.
In my opinion, if addicts expect us and everyone else to forgive them for their "past" they need to step up to the plate and do the same.
My guy has been sober 2 years but still is VERY intolerate of others shortcomings. It's still all about him, his recovery, etc. etc.
I wish you only the best, do something nice for yourself, and focus on what you want for your future. It will work out.