I to lost a lot of so called friends because of my disease. I wasn't invited to go anywhere either. I thought it was because of my rollabout. (which I still believe) Since then I found I only have one friend that wants to do anything with me and the other lives out of state.
I know it is hard to except, but it has something to do with them not understanding our disease. It is not like cancer or a broken bone. Try inviting some of them or even one of them to lunch and talk about crps. They will realize you really haven't changed. You just handle things differently.