Hi Shari,
Welcome to the Board! I just wanted you to know that I have a friend with Graves’ who went undiagnosed for YEARS (despite her eyes bulging out of her head) because she was gaining weight instead of losing it, and her thyroid levels were within the normal range but on the high side — poor girl went three years without knowing what was going on in her own body! Some people are just “contrary” when it comes to symptoms, I don’t believe anyone knows why.
Autoimmune diseases are related because they are caused by dysfunction of your immune system, and if your immune system is weak in one respect it may be weak in other respects or even be further debilitated by having one autoimmune disease.
Hope this helps — keep your chin up, I’m wishing you luck!
–Ski