It can be hard to go to another (and another) doctor when you have had bad experiences but you must find another one and try to give a concise description of your problems to a rheumatologist. There are clinics, call your country to find out where it is. Have copies of your bone scans to show the problem and keep costs down.
The really good medications offer financial help so don't give up. The links to SAA are excellent, go there.