I recommend social hobbies. Mine are BJJ and Magic the Gathering. BJJ is great because it can be highly technical but you will meet people way outside of nerd circles. My kids do it and love it as well. It is a hard thing, too, so it keeps the ego in check. You have no choice but to be extremely, intimately close with other humans. The friends I am making are great. There are plenty of other hobbies, but start there.
Edit: (start by investigating social hobbies)