So I have a friend with Hashimoto's. Before finally being diagnosed, she had a long history of being misdiagnosed, blown off, and having her symptoms dismissed as nothing. After being diagnosed, she connected with a number of other Hashimoto's patients and sufferers of chronic illness in general and found out that pretty much everyone she's talked to has the same stories. Constant invalidation, ignoring of symptoms, doctors just plain not listening, until they finally find someone who actually knows their stuff.