it’s hard to differentiate what is purely psychological and what is physical. However I believe that a lot of what is understood as psychological problems (anxiety, depression) often cannot be addressed or treated properly unless the health and balance of the body is also considered. If you have been able to overcome some of your social phobias on this diet then there’s your proof that this approach is working for you. And that’s great.
I also had social anxiety for years. I went to psychotherapy for a couple of years with no help. I finally accepted that this was just the way I am and that this is how things would always be for me; that I would always struggle to just go to the shop because of anxiety attacs, that I would always get this nervous sweating when just talking to people. However after a while on the Candida diet I noticed that I was getting calmer and my social anxiety was disappearing. This was just an added plus really since I had long since given up on ever finding relief from my anxiety. I was primarily addressing the physical symptoms I was suffering from. But from my experience there is a direct relationship between the health of my gut and the state of my mind.