^ Maybe give him a chance to learn a few things. True, though, one does need to be careful with tone of voice and choice of words to avoid looking bigotted when discussing a controversial topic.

There's a whole range of sexualities, ranging from straight to gay men, then to gay men who sometimes dress as women (called crossdressers), and finally to genuine transexuals, who experience gender dysphoria, a condition recognized by the medical profession and which is not just an "act". I tend to look at transgenderism as the end point in a continuous spectrum of sexuality. Try to get some facts about it, if you're interested in learning.