Real ways I made friends as a transplant in a new place:
Non-staff people related to my workplace
Nearby events that people related to my workplace knew about
Meetup.com
Church events (depending on the activity or group, they're happy to have you even if you don't believe what they believe or literally never went to their church a single time—in my case, because I can't due to being a weekend worker)—ironically, I met and befriended a nonbeliever who was also a guest at such an event, so never say "never"
Friends of friends (new friends who they become with, and then introduce me to)
Reddit and other communities (finally had a redditor over at my place from states away recently for the first time, which was interesting and fun)
I would probably add Facebook events and maybe a calendar of local events, such as activities at nearby libraries.
I wonder if you're able to scrounge up enough savings to move to a less-desolate area. Do you WFH?
I relate very much to your disconnectedness. It took me some time to realize that I was known to her circles as my "ex-wife's husband," not really as an independent being, so when we split, they stopped talking to me (well, us both, because she cheated and was adamantly unapologetic about it).
If you wanna try out titles on Board Game Arena, I have a premium-subscription friend in another state who would be happy to have you join us for games online from time to time!
As for IRL cost-saving events, I have friends over, or go to them, for a home-cooked dinner/potluck and a movie. There are streaming-service free trials and DVD/online movie services from libraries (such as Hoopla Digital and Kanopy) which should be able to help you avoid paying a cent. Hiking and board games are also cheap or free.