Hey Tumble,
As a former, recovering isolator, the urge to seclude myself didn't just go away when I stopped drinking. Obviously, isolating was part of my alcoholic routine. I only drank alone. I didn't want to deal with other people. It was just me and the bottle, and I was fine with that at the time.
So I got sober and those urges to withdraw were still there. I still fight them now. But when I push myself, I find I am the happiest when I'm surrounded by people who care about me. Sober people.
Sometimes it takes a little effort. I learned early on, sobriety can just be plain uncomfortable at times. But the payoff is so worth it. It's a LOT easier to push away thoughts and temptations of isolation and drinking when you have a sober friend to call or hang out with.
But I do think you made the right choice in skipping the party. That's not isolating. That's common sense for someone who only has a few months sober.
Keep it up. Not every sober day is going to be something awesome and magical. Sometimes the days are just blah. But blah is infinitely better than drinking away your life. All the best
