I also have some permanent health issues (not as serious as yours probably, but still) and I totally get the frustration of people applying wishful thinking to your situation without having any experience with the kinds of problems you're facing (as is happening in this thread).
I know it's not what you asked for, but feel free to drop me a line anytime if you need to talk to someone who has at least a slight chance of getting it. I can be reached on gmail under the same username.
If you have no in-person interaction that you know you need, are you just never going to go find it? Where do other people get it in your area? Church, probably, since you're rural. I'm going to go out on a limb and guess that you aren't interested in religion, absolutely hate where you're at, and probably the people, too, but I beg you to call local churches until you find one that can help you attend and where you feel welcomed.
Yes, I get that a lot too, and it makes me more depressed. If you're someone who's in the process of extricating themselves from a religious upbringing, this isn't a fun thing to deal with in addition to "regular" mental health issues.
What is helping me is:
* removing toxic parts of my life as much as I can.
* proper diagnosis and medication (the revelation of a late ADHD-Inattentive diagnosis is life-changing)
* meditation (Kabat-Zinn style mindfulness, warning that in my experience not being treated or missing your meds for anxiety/depression may make this a frustration engine)
* forgiving myself for not being more proactive (the hardest one)
* focusing on getting my son out to play with other kids (helps meet people with the same time-schedules)
What doesn't help me:
* Not taking my meds.
* Making extravagant plans. (Big things are more intimidating and generate avoidance).
* Cursing the past. (Mistakes were made)
* Going to church. (Attending a ritual gathering as a nonbeliever can be an incredibly isolating experience.)
Admittedly, the largest Fraternities have religious components themselves (the Freemasons, especially), and Churches themselves at times have fought the big Fraternities as "competition", but arguably the big Fraternities are kept separate and distinct from Churches for strong reasons, and tend to sway more secular with the biggest religious ties being calls to charitable service.
I've often wondered if it was possibly past time for a revival of the Oddfellows in America, which at one point was a huge entirely secular Fraternity (whose biggest remaining impact is a lot of fascinating 1900s-ish architecture in most major American cities): https://en.wikipedia.org/wiki/Independent_Order_of_Odd_Fello...
There's also a lot of interesting similarities to classic Fraternities/Unions/Social Clubs reflected in cosplay/fandom Unions and Social Clubs such as the multiple Starfleet Fleets (including Barfleet), the 501st, the Ghostbusters Locals, etc. Admittedly fandom/cosplay can be their own religion of a sort, but such things are extremely secular.
When I was lonely and isolated (less then you), arguing on the Internet helped. It is not same as real communication and friends, but it more then nothing. Keeps you from loosing it entirely. Writing is communication too, altrough less effective.
Another weird thing was that when I finely had chance to communicate, it was tiring because I basically forgot how to do it. If that happens to you too, that is ok and normal. Don't get discouraged when talk won't go smoothy (as I did).
I wish you good luck, that something around you shows up.
I really wish people would not do the "you have to work at it and it's worth it" thing as if someone in my position is lazy or doesn't want to have a better life. They keep throwing out things they think are so simple and obvious but can't seem to accept there are real, practical reasons certain things won't work. In addition you can't force someone to like something they simply don't just because it's "available". Please believe me that none of this is my lack of effort or attitude. Nobody would choose this life if there was a realistic way out but many people live like this. I do the best I can but it's crushing.