Fibromyalgia pain sure is excruciating. Stress increases the agony, and the agony leads to stress... it is a vicious cycle. But it is in our hands to not get stressed out due to Fibromyalgia.
Sure it is easier said than done. But I am suffering from Fibromyalgia and I know exactly how it is. The moment you start feeling that you can't take it anymore, you are letting the condition worsen. When the pain becomes so unbearable that you can't think of anything else, just indulge in some mild activity that relaxes you instead of thinking more about the suffering. Read a funny book, watch a comedy show, go to a spa orr simply take a nice hot water bath.
Just do not look at Fibromyalgia as the end of everything. Find out something positive about it. There's definitely at least one thing you can do when you are unable to do so many things. Like for me, had I not had Fibromyalgia, I might not have started an awareness drive. I started reading on it day after day, and I know what I must do now. I look at it as a purpose to do something new.... how about you?