I do wonder if there's a benefit in terms of being able to deal with your changed life i.e. from psychological interventions? However, I don't have any objective evidence to point to; in fact, if this was assessed then I wouldn't be surprised if it amounted to little more (or even less) than a caring Doctor showing an interest in their patient.
I have followed CBT/GET at Het Roessingh in the Netherlands and the experience was harrowing both from a physical as from a mental viewpoint. There was a lady there that had applied but was unable to partake in the activities set forth who was basically shamed for not being able to do so.
My experience there was milder at the time, but I did learn from them that I should be able to control my disease if I'd follow their instructions and increase my activity with small increments starting from a baseline. This was more or less pounded home continuously, if you want to get better you have to take charge and you have to follow our instructions.
So naturally when I didn't improve over the years but actually got worse every time I tried to push my activity a step forward I blamed myself. I followed the course there age 21, we were on the first floor with our group and I was allowed to follow the course with the grown-ups. There was a group with youth downstairs that had an even more intense and more prolongated treatment with CBT/GET, it could run well beyond half a year.
I only started to let go of my selfblame after my mom had bought a book from Michael Maes, detailing amongst other things why the BPS approach didn't work in M.E. At first I didn't even want to read it, but my mom convinced me to do it. This was about 5 years after the treatment I think. I still have lingering issues caused by their treatment which lead me to doubt and blame myself for things I know I shouldn't. But it's a reflex back to 5 years of doing my darnest on this wretched treatment of theirs.
I have seen 2 psychologists after my CBT treatment. Or well, one during the 5 years that I was still trying to better my condition myself. He wasn't helpful at all and even called me a stubborn bastard for not taking his bs wholeheartedly. He also was all about improving yourself through the magic of CBT.
The other psychologist I saw was one I had to visit because of my application for benefits based on my illness, wajong it's called in the Netherlands for youth. She asked all sorts of questions and I answered them truthfully, when I told her that I was very quiet in school from 13 years of age and didn't really stand up for myself is when she sprung to life. Just from talking to her it should be evident to her that I was perfectly able to stand up for myself but she offered to treat me for something I had problems with about 15-20 years ago anyway. She told the judge that was appointed my case that I wasn't lying about being sick and that I should be treated with CBT. Luckily I had already followed a treatment with that, so I wasn't ordered to do more of it. I wasn't going to anyway, benefits be damned. So eventually I was deemed sick, but I was deemed well enough to do work in a closed room devoid from sound or other stimuli for 45 minutes a day. Benefits denied.
This was before the change in stance regarding M.E. in the Netherlands though.
My experiences with psychologists are that they are at best unhelpful, at worst that they are harmful because the ones I have encountered have a very firm believe that you can overcome basically everything with the right training and/or mentality.