I don't live in Pittsburgh but grew up nearby. As a transplant in my 30s I've found the gaming community to be the most enjoyable social experience for non alcohol based activities. Specifically I play a game called blood on the clocktower that I play with a nearby group I met on Reddit. I also have a dungeons and dragons group I play with weekly. These semi structured events force socializing in a unique way that's engaging and light hearted. I would try to find groups that do things like this if I were in your shoes.