It's never too late... well, almost never; I guess if you are currently falling from an 80-story building it could be too late... but really, almost never. People have come back from being in prison, for example, and that's about the lowest a person can go. Lots of people have come back from being homeless. There are people who've graduated from college after failing out, or gotten and kept a job after being fired; and most people who get a mental illness either recover or successfully manage it long-term.
I don't know if you are like this, but often times when I feel like that, it isn't that there really isn't a way out of whatever situation I'm in, but that I simply can't see it. I think linearly, so if my original solution gets blocked, I often gravitate immediately to "impossible". It usually isn't impossible, though; and when it is, there is often another equally good path leading someplace else just as interesting.
Many of us do have nobody but ourselves to depend on. That can be frustrating, and it can make things a lot slower and harder; but it can also force you to learn things that are difficult and necessary.