I think what everyone is saying here re: he needs to focus on his recovery is very true, but that said, I definitely understand your feelings. I think treatment, even when you're happy that the person is doing it and you know it's the only way, can bring with it its own issues for the loved ones of the A.
My BF recently went into treatment and had his first one on one session with the therapist, I asked how it went and he said it went great, that he sat down and told "the whole story, from beginning to end, everything." The reasonable part of me is glad that he's being open, I'd be highly disturbed if he wasn't, but I'd be lying if I said it didn't sting. I certainly haven't been able to get "the whole story" out of him.
It's difficult. You're being put through (and have been put through) a lot, while getting very little in return. It's very hard, and for what it's worth, I can relate. *hugs*