I deal with several autoimmune conditions. Systemic lupus [diagnosed in 1988!], fibromyalgia, gout, and an ultra-rare kidney disease that has led to dialysis.

Being under the care of a great therapist has helped me. Beyond that, doing journaling has been helpful to get thoughts off the hamster wheel of my mind and onto paper. Being creative in some way can also steer me to a more positive frame of mind [gardening, crochet, quilting, artwork]. And reaching out to help others as I can. It can be as simple as helping someone reach something on a shelf in the store. It makes me feel good, wanted, nevermind how it helped someone else!

I hope these things will help you. Give them a try, if you haven't. If you have but have not been satisfied with the outcome, try again.
Ginger