Oh sweetheart, I think that we might be twins too.
You can't go back to change
everything in your life, because then you would never have come to this forum, and then who would come by and make me smile when I'm trying to feel sorry for myself?
And maybe moving into a place by yourself isn't such a bad idea. You'd be shocked at how much stress can be dropped when you aren't living under the watchful eye of others. Suddenly you can do/eat/say whatever you want in
your home, and you no longer have to explain yourself to others. It gives you much more control over your life. I lived in a tiny two room apartment for over a year, then moved in with my current roommates, and now I can't wait to be back in a tiny apartment again.
As for the pain problems, well I don't know how to fix those, but don't give up. I will hope and pray for you.