I'm also less social since stopping drinking and very uncomfortable in groups. I don't like being around people drinking heavily either, not because it triggers me anymore butbecause there are other,more enjoyable things I'd rather be doing with my time.
Maybe your tastes are changing now you're sober. If it is causing you such pain and worry maybe take a step back and re-consider if this is something you really want. I kow what I used to like when drinking isn't what I like doing now