I'm two years ahead of you in this journey. I got divorced after just over a decade with my partner. Social engagements to me were always ad-hoc. I suck at planning so I often found myself more alone than I'd like.

Looking back on the last two years and auditing what worked, I would say routine and lingering were the most important thing.

Trying new things is mentally draining and labor intensive, this is a fact of life for many. What worked for me was finding something I enjoyed (exercise classes) and doing it consistently multiple times a week at the same place for months. With repetition, it's very easy to make new friends. Complaining about one exercise one week turns into making comments about the music the next, and all of a sudden you're getting coffee with friends.

At the start it was very difficult, and I was very bad, but now I'm part of a community and have many close friends. Its a hour per day most days of the week. It's also a jumping off point for everything else social. It provides purpose and self-confidence. Which are prerequisites for everything else meaningful in life.

One other thought to drill deeper into regarding lingering.

I'm the type of guy that always moves with purpose. When I'm done doing something, I'm quick to leave. Looking back on my life so far, I think this has often been mistaken as antisocial.

Every event involving humans is default social. Leaving quickly precludes much of life's social whimsy.

I'm much the same. It's hard to notice. Coming up having onsites with three and four and five consulting clients in a "normally busy" day (you want 'high touch?' I started before smartphones!) taught me to associate just that purposeful attitude with the satisfying knowledge that I probably wouldn't end the day running further behind when I started.

It's a good energy to bring to work or to a crisis. Everywhere else? Maybe not so much. I appreciate you mentioning it here; it can serve me also, as a reminder to work on that.

"With repetition, it's very easy to make new friends."*

*Assuming you possess the necessary social skills.

I've trained BJJ consistently for over 4 years now. I think fondly of all the people there and feel accepted, but we barely talk, and I'm unable to participate in the locker room camaraderie.

This is probably not a problem OP has, I just felt the need to complain.

I think social skills are mostly just like any other skill: you have to practice them to get better at them. And while you might be more or less naturally gifted at any skill, there is a minimum level which every abled human out there can reach with some effort. You will never be a showman,a car seller or the king of the party but you can have interactions with other human beings and connect with some of them. Just like you can learn to play guitar, juggle 3 balls or do basic algebra.

The other people probably just think of you as some stoic guy and respect you for that

Wonderful advice Geoff, that's the same kind of thing I started doing when my relationship broke down. You find your community, and the rest will come.

you hit the nail here.. repetition is key! that’s what happens at a workplace or school. You show up every day, do your thing, and have small interactions here and there. Over time, those interactions grow, and you get to know each other on a deeper level and become friends.

This can be replicated with similar activities that involve a schedule, like joining classes, volunteering, or whatever else fits that kind of setup.

Within volunteering, I think it is worth shopping around. Some organisations do not treat volunteers well, and some are great social experiences.

I would try and get something where you can see the results in front of you. I worked years ago at a soup kitchen for the elderly and felt much better for it, than working in a charity shop on a till and feeling like I was just a worker unpaid.