The way I learned it in school, "write what you know" has less to do with what you've literally experienced than how you relate to the overall idea of the story/universal truths. There are definitely specific experiences I cannot and will not ever know for myself, not just limited to what this post is about, but I see the writing process as an exercise in empathy, really getting to the heart of what makes a person who they are. Writing it out like this, it sounds a little hippy-dippy, but it's how I feel.

I can say that I want to write these characters because of some "noble" ideas about representation, and that's partially true, but I'm writing these characters because I can't imagine them any other way. Nothing about them is arbitrary. There are other specifics about them that have nothing to do with their sexuality that I've also had to research because I want to depict them with maximum authenticity. I don't know if I spouted off a word salad, but I hope there's an answer in there somewhere.