There's nothing you can do to change what happened in the past but you can treat every new day as a new opportunity to try to self actualize, following whatever path to do that seems best to you.

I spent a solid chunk of my 20s being an alcoholic in a desperate attempt to hide from myself. Late 20s (like 28-29) I finally moved to the right place, put in an exhausting amount of work into finding local connections, I'm doing a lot better now. Eat healthy, do some kind of physical activity if you can, see if there are any groups near you that share in any of your interests, don't expect it to be solved right away it takes time. Enjoy being at the early side of old people "I just truly don't give a fuck" mentality because that can carry you past a lot of social anxiety. 16 yr old at the MTG table says you have a garbage deck? IDGAF, give them a "I'm old enough to fuck your mom" glare through your beginners crows feet. Bond with the people who think that kid is a dipshit. Being in my 30s now is way better than my 20s I'm happier and healthier (save for COVID giving me fucking asthma never used to need an inhaler)

In your 30s you can still do almost anything, so yeah :)

I went skijumping last year, which was a childhood dream of mine.

Same. I'm 3 years younger, but depression, anxiety, and the resulting lack of any kind of sense of mission have made me so miserable. The lockdowns tore down the resemblance of a social network I had, and now it feels like there's nothing left. I'm trying to get better and to change, turn my life around, but it's hard. I don't have any encouraging words. Just know that you're not alone in feeling like that <3