I had a similar problem this year after having moved to a new country, working a remote job and separated from my partner. Having had a terrible social life since I was a kid, I knew it in my bones that I'd have to find myself new friends or else. So I did - I renewed my relationship with old friends, joined a book club (was a big reader as a kid), and my dog helped me make friends at the dog park.

I find it interesting that I've thought about the exact social mechanics of making friends before as well - low stakes in person common context where you meet on a regular basis is key.