Hello, I do sympathise with you - telling you that her other patients have all improved within 2 years is unkind and hard to believe. I wonder whether those who have not improved have changed doctors, so she doesn't know about them. It sounds as though she has at least been willing to try you on several treatments which is good. I think it's good that she's honest with you that she doesn't know what else to do. After all, there is no known cure that works for everybody, or even for most people, which is why most of us are still sick.
If you were in the UK, all you'd be likely to get is something to help you sleep, standard pain killers, and bad advice to exercise more.
I wonder whether you have tried the non-medical approach, focusing on getting enough rest using pacing, a heart rate monitor to help you work out when you are overdoing things, or 'aggressive rest therapy'. There's lots of discussion of these on other threads here.