Hi there. I really sympathize with you and all the pain you are dealing with. You need sleep if you are going to deal with this intense pain.
Have you ever tried Zopiclone? It is wonderful. I'm not sure but does relaxing in an epsom salt bath before bed calm you somewhat? Zopiclone is a great sleeping pill and hypnotic. It is known for giving us good REM sleep. Would your doctor consider a month trial? Let me know if that helps. Good luck.