Well I think it totally sucks that the man you have loved for so long decided to get sober when it was just for his own benefit, instead of while he was with you. Now you're left feeling as if you caused his drinking, which you did not.
I think you got the short end of the stick here.
I think just about everybody gets the short end of the stick with an alcoholic spouse.
One caution though--if he can't figure out why he drank, then he might go back to it. A few months isn't much time. The true test of his sobriety is going to be year 2, or year 6, you get the idea.
I hope you can now focus on ways to make yourself happy. Get a little selfish!