I use Facebook for 2 things. Still coviding groups and marketplace. There's almost assuredly a group for your local area (state, metropolis, etc) and from there you can look for the off facebook groups.
If you have a mask bloc in your state you can message them and see if they can point you towards groups they coordinate with.
You can also try the Refresh Connections app. I signed up for it myself, but haven't really done much with it.
R/ZeroCovidCommunity on reddit, which is becoming less and less zero Covid and more being aware of Covid while complaining about other people's precautions, unfortunately.
I don't use them but there's also r/masks4all and I think a subreddit for lovgcovid victims.

Yeah, that's basically all of reddit now, unfortunately. The automod flags my shit all the time and they don't get approved until the conversation has moved on.
