Well, my partner (genderqueer/androgyne) previously identified as a lesbian (as did I).
When I came out as trans, I wasn't sure how Ash'd take it, and sie even admitted that sie didn't really know how to feel about it, and "what" that made hier: lesbian/straight/other?
After a lot of soul-searching on both our parts, Ash decided that sie loves me for me, for who I am inside, and that's not changing. Sie's modified the label of hier sexual orientation to "queer" (which is separate from hier genderqueer/androgyne gender identity, I might add), and I think sie basically see's me as the "exception" to hier rule of primarily being attracted to women.
I can tell you, at first I was really insecure about whether Ash saw me as a "real" guy or just a girl who goes by a male name/pronouns, but I really do feel that sie completely sees me as male. One time, someone mentioned me by my birth name, and Ash was like, "who? Ooohh, James!". Sie had kinda mentally blocked that name in reference to me, since to hier, I'm just James, I'm completely hier boyfriend/male partner, I'm just a regular guy, etc.
I've also adjusted my sexual orientation to "queer", not entirely because Ash is GQ/andro, but also because I don't feel like my orientation is 100% one way or the other, and I certainly don't feel like a straight, white, male. I identify more personally with the label "queer" as it allows for some flexibility in definition, and accounts for the fact that even as trans, I'm still a part of the larger LGBTQ community (yes, I know, there's controversy in that, but I feel happy being a part of that community - for me, ymmv).
Anyhow, back to the topic at hand. As far as sexually, there was some trepidation at first with Ash seeing my "parts" as male. But I think once sie got used to seeing my biological parts as the male equivalents they are to me, and once sie got comfortable being intimate with my "detachable" parts as well, it seems that we've really hit a much more deep and personal level in our sex life. We're both able to be completely vulnerable with each other (which is very important to intimacy, if you ask me), we both feel completely attracted to each other and know that our partner feels the same about us. And trust me, sie relates to me and my body sexually as a man, not as a woman with a guy's name.
I think some people have much more rigid senses of their sexuality, and that's okay if that's what's natural and valid for them, but because both Ash and I were able to be somewhat more malleable throughout this process, I think we've found a comfort and acceptance that really works well and has strengthened our relationship as a whole.
So the "no relationships last during transition" thing seems to be a fallacy, at least in my experience. This does not mean that all relationships last through transition, because obviously there are many people out there who are not able or willing to adjust their frame of reference or be attracted to their partner's target gender. I absolutely respect those people in that situation though, because I understand that just because we were able to be flexible in our orientations doesn't mean that everyone is able to be. I think some people just authentically are at one end of the spectrum or the other, and cannot be something they're not. Since we were already in the murky "grey area" anyhow, it wasn't much of a leap for us.
Anyhow, just my two cents.
