I'm sorry you are going through all this. The first thing I would do is try to find a teaching hospital near you. I would also request a full blood work up, preferably from a hematologist. You may have a severe vitamin or mineral deficiency as the driver in your health issues. You could also have inflammatory markers or something else that a hematologist would uncover. Then I would request a full body scan to see what is going on and where. Your back is not going to feel better until you can start getting your weight down. If any of your current doctors don't take your issues seriously, then find another. Don't settle for substandard treatment.