I recommend reading "healing back pain" by Sarno which talks about this phenomena. The book is mainly about back pain but it applies to all kinds of psychosomatic pain. There's also a free forum with free guides and support from others who have dealt with the same: https://www.tmswiki.org/forum/
In particular the success subforum is very inspirational as it contains posts from peoole who have resolved all kinds of pain syndroms that they originally thought were caused by structural injuries (including rsi).
I feel like a shill writing this and I remember I thought people talking about this theory back in the day were paid shills. But I promised myself after I got rid of this huge burden due to the psychosomatic approach I would let people know about it no matter how many downvotes I get.