Girls, gurls, grrrls
I'm a 28-year-old straight guy who's been using the internet to hook up pretty much since I started dating. It works for me because I'm a bit shy in person and I have a job that I need to get up early for so late nights cruising at bars are not for me.
Recently a situation came up that I want an opinion on. I was chatting back and forth with this girl and eventually we exchanged photos and agreed to meet when it was obvious we both found each other attractive. I want to make it clear at this point that I am not homophobic or transphobic (a word I had to learn in unfortunate circumstances as you'll soon see) but this girl turned out to be transsexual, something she neglected to tell me when we were flirting online. I think this is something you might want to mention before you hooked up with someone. It made our date awkward to say the least and suddenly I was put in a position of being treated like a jerk because I had an issue with it.— A Good Guy, I Swear
While some trans people identify very openly as such, others identify strictly as the sex they present (which makes it kind of odd that she should be throwing the word transphobic around, but let's not get me into all kinds of hot water with you). There are differing opinions within the community on disclosure, but here's one from trans activist Rebecca Hawks: "While you're allowed to have your preferences for any type of woman, you need to recognize that this is your issue, your preference, your expectation about what you're getting and you can't be blaming this woman for being honest about who she is."
Hawks talks about how divulging suggests a liability. "It's like putting caution tape around oneself. Can you blame any trans girl or trans guy for not wanting to do this right off the bat given the total lack of savvy that most people have about trans issues? [It] plays into the belief that being trans is something wrong, something that cissexual people need to be warned about before proceeding. It's a nauseating, self-deprecating act that just feeds into these bigoted ideas that trans women are not/less 'real' or 'valid' women. What is the difference, really, between a hot post-op trans woman and a hot cis woman? She can't have kids. That's about the beginning and the end of any downsides. And there are some good sides that he may not anticipate, like having a hot girlfriend who he may be able to more closely identify with the 'shy' sorta guy he describes himself to be."
Hawks gives you credit for not fucking up your pronouns but says, "the only thing he should feel sad about is that his prejudice has prevented something good from happening with this girl he is attracted to."
I'd say you've learnt a valuable lesson about the great variety of women out there and if you have special preferences, you should make them clear on your profile.