Depression does very often go along with it, especially if you have fibromyalgia too, which I do. (Doctors seem to treat CFS/fibro as overlapping illnesses/syndromes.)

I had my first major episode of depression about 4 years before the CFS started.

Really the only reason I made the comment was that my depression seems to not respond very well to meds, so sometimes I wonder if I'm misdiagnosed.