It's horrible having so many parts of you that don't work properly, I can identify with this so much. One thing after another, and as soon as one thing feels a bit better something else gets worse.

At some point there will be an improvement without something else regressing, at least for a while. I know how frustrating it is no being able to do the things you want to, or should do. Do you have plenty of sick pay available? Not having to worry about money would be a plus.
Take good care of yourself, physically as well as mentally. If your hole has turned into a safe hiding place, I have some soft velvet that soothes me - maybe you'd like some?

Bluegrey