Dear Mr. MacFarlane,
Oh where to begin?
Not being trans yourself, I don't necessarily expect you to be able to recognize a sympathetic portrayal of a trans character when you see one, and given that, I don't expect you to be able to write one either. Telling us we're stupid because we don't recognize how truly "sympathetic" your characterization of transsexuals is makes about as much sense as me trying to lecture you about the technical aspects of animation. You're an animator, you know about animation. I'm a transsexual, I know what hurts and what doesn't when pop culture decides to talk about me.
And trust me, being characterized as a monster so completely disgusting that I could provoke a heterosexual male to vomit hurts. It very likely hurts cisgender women as well because what you're really saying is that regardless of any other virtue a woman may possess, the only thing that makes her not a disgusting vomit-inducing monster is the genitalia she was born with. Ultimately, what you've done is deny me my identity; by saying that you could not or should not be attracted to a transsexual, you say that I must somehow not be a woman. What your portrayal is sympathetic of isn't transsexuals, it's sexist transphobic homophobic men.
Your mistake is that you can't imagine any heterosexual man wouldn't react in exactly the same way as the character in your show. But there are men and women out there for whom their partner's past is less an issue than their present, and for whom biology is less important than their heart. But their willingness to love is trumped by the intense social stigma that comes with dating a man or woman of transsexual history...a stigma your show shamefully endorses and perpetuates.
All people are worthy of love, including transsexuals. And until we live in a world where transsexualism is seen as a natural part of female diversity many of us will live lonely, unloved lives. You had an opportunity to help us all take a step forward, but instead you chose to revel in prurient hate. And all for a cheap laugh. Congratulations.
P.S. I don't know why you're addressing your statement to the gay community, but thankfully they forwarded word to us. Perhaps you should, you know, do a little research about the minority group you intend to trample upon.
P.S.S. I don't know any gay men who have expressed disgust at or about vaginas. Plus, once again, you liken people to their genitals, as if that's all that's important to anyone. Seriously, grow up.