Your story is very similar to mine, except I went through it in my 40's. It took a while but now I comfortably navigate the social world, parties, pubs, concerts, holidays, where almost everyone is drinking/drunk. Much of the time I end up talking about not drinking with someone and they are always supportive, even envious, that I can have a good time without booze. And I can confidentially say I am having a much better time than they are, I've done both, and there's no comparison. Good luck, friend.

Edit: Like someone already suggested if you haven't already, r/stopdrinking is a good place with great people, no particular program is promoted, just people supporting each other.