"She was by that time fairly calm again. You cannot keep up fits of emotion by the hour. At any rate, with her, the fits of emotion were periodical and unexpected, though her colder passion remained always the same…."
No More Parades - Ford Madox Ford
(Sylvia Tietjens is the most intriguing of the three main characters of Parade’s End. You never know what to make of her which makes her my favorite character so far.)