Well, as a gay person, I want to throw my opinion out there.
I think there is, and should only be four sexualities: Heterosexual, Homosexual, Asexual and Bisexual. I think more common terms like pansexual, or the tumblr tier sexualities like Iculasexual or Gynosexual are just meaningless terms. You like men, women, neither or both. If you like things other than their gender, like their age or hair colour, that's a fetish, not a new sexuality.
I also think there's two genders. Male and Female. These do not have to correspond to your genitalia at birth, transgenders who identify as female should thus be approached like them. No one truly fits in with the stereotype, as every individual is different. This doesn't mean you're special enough to change hundreds of thousands of years of human gender-related values.
People who make everything about their sexuality or gender, no matter if it's one I consider real or fake, are incredibly shallow. I usually don't tell anyone I'm gay unless they ask (or I'm interested in them ( ͡° ͜ʖ ͡° )), and I have an incredible dislike towards the "flamer" community, a very vocal minority of gays that need to tell everyone "hurr durr im gay hurr durr homophobe hurr durr im better than you". I am more than my sexuality, and most of the time it's got nothing to do with the situation. I usually don't see the point in mentioning it.
Most importantly, I also don't harbor any distaste against people identifying as something I don't consider real. Sure, they're not perfect in my eyes, but everyone has flaws and just because they support something I don't doesn't mean they're bad people. As long as they're not constantly complaining about it and stuff, I'm totally fine with it.