I don't think it's odd that it bothered you to hear her called a boy, any more than I would think it odd if it bothered you to hear it constantly emphasized that she is a girl. Most people apparently do think of themselves as the sex that corresponds to their genitals, and that's fine--I don't think anyone would argue that life, for the individual, isn't easier that way! It's the "and therefore you must be/do/act such-and-such" that's the problem, and being identified by others can contribute heavily to that.