S.S.
I haven't been in your situation but I just wanted to say that from your post, you sound pretty content/happy in your marriage if you ignore the drinking problem. First, I wanted to say, is the drinking an actual problem (like he's an alcoholic) or do you just wish that he wouldn't be such a partier. If it's the former, you have to get him to see that it's a problem and help him get on the path to sobriety. If, however, it's the latter and it's just a personal preference that you have that he not party so much, I would continue to go to therapy and continue communicating with your husband so you can work out something where he doesn't feel stifled and you don't feel so irritated with his behavior. You two are separate individuals and so, you'll have to figure out what works in your marriage. I would hope that you wouldn't just jump ship though (assuming he's not an abusive alcoholic) b/c it really does sound like something that could be worked out with communication, therapy, effort from both parties, etc. Best of luck,
update: just wanted to say that i'm assuming he does his share of household chores, taking care of kids, etc. since you said you parent well together and he's a wonderful father. if his drinking/partying gets in the way of that, that's a more serious problem and you'll need to seek out help for both him and yourself to help deal with his problem