I hear you, hon. I hear you. I didn't have the same hurdles you do, but I am very familiar with the sensation of dragging myself through life by my fingernails. No hope, no prospects, no emotional reserves--only fear and a strong survival instinct.
I'll tell you the same thing my partner used to tell me: sometimes you don't digress OR progress. Sometimes you just "gress." You tread water and don't make headway. And as long as you don't lose ground, you...haven't lost ground. Just holding your ground can be a good thing.
He used to say that doing something that doesn't work is valuable intel. "Okay, now I know what NOT to do. I'll have to try something else."
He also used to say that sometimes you just need to take a break. Boy, was he right.
And I'll tell you what my therapist said when I was close to giving up: I know it seems like there's no light at the end of this tunnel, but there is--and it's daylight, not a train trying to mow you down! Even though you don't believe it, you can get through this, and you will get through this, one step at a time.