Yeah, it looks as if you'll have to wait and see. For what it's worth, my mom's first reaction was also one of support, followed by trying to talk me out of it. Finally I wrote her a letter explaining exactly why I felt I had to do this, and that seemed to get through to her.
A year later and my parents are finally managing to get my name right
most of the time, but are still struggling with the pronouns.

But at least they are seriously trying.
Sebastian - That sucks. I hope she eventually comes around, but it's not looking very hopeful, is it?