I think most of us have faced this Ben.
I think we relearn how to interact, but soberly.
It can take a while, especially if your group of mates remain the same, but like anything it does get better with experience.
I'm a far bit older than you so, for me, it was time to stop pretending I was 18.
Now, without being a recluse or avoiding situations, I'm a lot less 'social' - and I like it that way.
D