How to pick new social hobby in your 30s

Long story short I am recovering from substance abuse issues. I have to start over from scratch socially and make all new friends and human relationships with people. I don’t have any close friends just acquaintances. I’ve built up all the materialistic stuff in my life. Financial, job ect ect but now I’ve come to the human relationship part. I don’t let people get too close to me because I have a lot of shame and embarrassment of my past with substance abuse problems. I’m a pretty broken damaged person on the inside. I feel like if people find out the real me they will judge me and not want to associate with me.

But I have to try. Sitting at home by myself night after night is pretty soul crushing. I’m a single guy in his mid 30s looking for a hobby I can do socially with other people to meet new potential friends. I was thinking maybe an adult martial arts class but I’ve been too scared to actually do it. I feel like everyone my age already has families and obligations that keep them unavailable for friendships. I’m an athletic person so physical hobbies have always been my favorite.

Starting over in life socially in your mid 30s with no real friends, no support system, no one to lean on has been very difficult. When I start opening up a little bit with people I feel like they think I’m being needy and so I just don’t reach out unless they do first. I feel like I’m a burden on everyone else who is busy living their own lives.