It's difficult, and of course, I don't have the answers. One thing I'll say is that where you live can really have an impact. In my case, I grew up in the greater Chicago area. To this day I do not identify with that place, I find it depressing, horribly consumerist, there are too many people, and I rarely click with anyone and it feels like there is so much superficiality. And I dunno, just the land there doesn't work for me, the boring endless flatness, and the concrete jungle, is depressing. I moved away a long time ago, and ended up in a different place, a cool small city in the mountains, and life is entirely different here. I relate to people I meet, I have a strong community, great friends, people are positive and involved in the arts, it's like night and day and my quality of life is much better here. It plays a huge factor in my level of satisfaction from my day to day life.
The physical disability is something totally different, and I'm very sorry that you have to suffer that.

But at least COVID's end is in sight, so hopefully that will help with the physical contact. I also consider physical contact to be very important, I am a touch-oriented person, I like to hug, and I just have always wanted to touch/feel things as [part of how I interact with the world. The pandemic has been really weird for me in that I have to keep to myself physically,. I don't like it.
Yeah that is a big factor this past year, but it seems that there is a trend of increasing mental illness/depression/anxiety. Though to be fair, as I think someone else said earlier, it may be at least partly because there is a much increased awareness of mental illness and social acceptance. I know that in my dad's family growing up, they did not talk about it, it was considered shameful. His sister was bipolar and suffered massively and his parents refused to admit that she had any issues, and so did she, and so for all intents and purposes, from a statistical standpoint, she was not depressed. Yet she was, very much so.
Maybe some people are depressed because no many people are dicks these days... like you just now. Or maybe so many people are dicks because they're depressed?