Interesting thoughts @Killpond and @Faye.
This is my own personal perspective, coming from a straight male. Not that what I am or who I am matters, and I'll explain why.
Everyone has their own reasons for Roleplaying, and those reasons usually dictate at what level I am willing to interact with other roleplayers. My own personal reason is a love for writing. I like stretching those creative muscles. I like exploring characters, creating nuanced characters, and telling stories that hopefully are engaging and moving for others. I look at myself, in RP, as I would an author of a book. Our attachment to our characters is not nearly as strong as the attachment to our stories, and sometimes to tell the best story, you have to let that character grow, walk into their own folly, and die at the hands of the narrative. The most fun for me in it is really just watching those stories evolve in the world around them and letting them go their natural course.
Its for this reason that I don't have the same 'heebey jeebies' (not your words, mine.) when writing with other characters of the same sex, or opposite sex, that I feel a lot of straight male roleplayers do. I definitely never go as far as to asking whether another character's player is male, female, gay or otherwise. Because then I breach that thin line where my personal OOC desire begins to direct the motives of my character.
This is to say, that I think most people that come into threads like this and post about a need to find an IC partner are a very different kind of RP'er. One that looks to roleplay to fulfill a need, or to fill a social gap that they may not otherwise find in their own life as easily or as comfortably. That might come off initially as a dig. But you shouldn't take it as such. There's nothing wrong with that in my mind, but be clear on your intentions OOCly and the intentions of other people OOCly, and respect those players limits, wishes, and RP style. Because that kind of behavior, while not a bad thing, does raise flags for those of us who want nothing more than to tell a good story. That is a generalization, not an etched in stone rule.
So as for my feedback and my advice, I give it as a writer, and not someone needing to fill a connection I crave on a personal level.
Let it happen naturally. Don't go looking for it. Focus on your character, their story, and where that story leads them. You never know where that path will take them and who they will meet along the way. But I promise if you take that approach and try not to focus on finding an IC Partner, when you finally do find someone worth writing with on an intimate/romantic level, it will be that much more powerful and meaningful.
Good luck! May the odds ever be in your favor.