This question & answer moved over from my formspring account.
What are the differences between CFS (or GRV?) and fibromyalgia?
I’m not an expert on this; I have ME/CFS, but not fibro, so I’ve read far less about the latter.
In practice, it seems like if you have mostly pain, it’s fibro, if you have mostly exhaustion, it’s CFS. But now that we potentially have a pathogen identified, I’ll be very interested to see what is discovered about the prevalence of retroviruses in fibro patients. Maybe they’re two separate things; maybe they’re just different presentations.