Not a single research believes that CFS is imaginary, even proponents of the cognitive behavioral model of CFS. They say that psychiatric factors influence the illness. Even Wessely himself published a review saying that the immune system was "almost certainly" involved in the etiology of CFS. This "all in your head" accusation is just a strawman.

I think a lot of militant patients incorrectly believe that there is some arbitrary division between mind and body, and that the mind cannot cause physical symptoms (which is, of course, demonstrably false). I think this is caused by a general prejudice against mental illness, as well as a general misunderstanding of how the body works in terms of psychosomatic interactions between mind and body.