I believe this is 100% true.
As much as it sounds a bit like “feel good pseudoscience”, ALL of my recoveries have come after persistently seeing multiple doctors and talking to therapists.
It wasn’t any specific treatment or advice they gave me, but I believe after a certain point my pysche gives in to being so cynical and depressed all the time, and accepts the doctors telling me that on a surface level I am fine.
After such recoveries, I still have certain symptoms, but my anxiety and sleep and general behavior is MUCH better. Which creates a positive cycle of a lot of my other symptoms.
I do believe we have some epigenetic/endocrinologic problems. But I believe one of the biggest manifestations of that disbalance is on our neurological system. Melcangi’s and other studies demonstrate this as well, with the deficiencies of crucial neurosteroids in our system.
And as @fixit has said, we know that our neuro system is influenced by vicious or useful cycles it’s impactes by our own thinking and behavior.