I'll assume that her specialty is regional or 19th-century and not New England or 17th century.

I wouldn't take it too personally, though: There does seem to have been a fashion lately for back-diagnosing famous people with various conditions (sometimes at the prompting of medical scholars and sometimes not). Zachary Taylor and the alleged poisoning. Lincoln and Marfan's. Probably every eccentric in history has been posthumously diagnosed as Asperger's or bipolar disorder.

People get interested in something and then try to explain it within the boundaries of their own expertise and experiences; if you're a doctor or biologist who gets a bee up his nose about something like that, the odds are pretty good that you'll look for a genetic or toxicological cause. (I was a history major. I'd look for a cultural cause. My brother is an archaeologist. He'd look for a cultural cause and then go excavate some cabin foundations, looking for evidence.) Most of them seem not to pan out, though.