I got to wondering originally if maybe she didn't have an over-active thyroid. I used to know somebody who completely whacked out one day, and they were thin as a rail (just like her) and had bulging eyes (just like her) and were given to "weird mood swings".
I knew someone like that too, in college. Only in her case, her thyroid was failing completely, not being over-active. One day she was perfectly the normal; the next day at dinner she was raving like a lunatic, convinced that her professors were conspiring against her, all the girls in her classes were lesbians who wanted to seduce her, and saying the most random, incoherent things like "it's OK that I'm telling you this because there are 3 of us at this table. But if there were 5, that would be scrupulous." It was very frightning. I had no idea what was going on - she was a very conservative and devout Catholic, so drug use didn't seem likely. Fortunately she went to the hospital in time, because she actually came very close to death. She had to withdraw from college completely to recover her health and I don't know what happened to her after that.
For all you reading this, if you ever notice a friend or acquaintance acting in such a bizarre manner for no apparent reason at all - please get them to a hospital right away. It could mean the difference between life and death.
What "physical and mental issues" would require inpatient treatment?
I think that by now the family would have leaped on the "blame the thyroid" bandwagon, had that been the case.
Nah, she's just nuts.