Exercise + socialize
Meetup.come and facebook groups can be a great resource. Try something that freaks you out a little bit.
I <3 acro yoga, group and solo mountain biking, and group and solo rock climbing. Maybe one more of those would work for you. Maybe you should find something else. Ultimate frisbee, geocaching, group fitness classes, group hiking. There are a lot of exercise + socialize options out there if you go looking for them. Do it and I bet you’ll thank yourself for it later on down the road. If you feel uncomfortable putting yourself out there and trying something new than just try to remember how uncomfortable you are with the thought that there might be something more out there for you. I bet that there is.