Saying it is discriminatory to not date a trans person, is basically saying sexuality is a choice that you should 'get over' if its going to upset someone else. Which is clearly ridiculous.
I may get a little too worked up in this thread due to knowing loads of lesbians who have already been called transphobic/bigots over this issue, and one who was seriously assaulted due to refusing a penis that she did not know was there until she was alone with the person