Thank you for your reply!
We have talked about erections; but she's not getting them right now and still doesn't want sex. We have had long periods of time where she is very sexually open; I guess part of what helped that was I always knew she was transgendered but when we met she wasn't presenting as female, so I encouraged her to do so, knowing that would make her feel more like herself (and also I'm more gay so in a way it was also selfishly motivated) and always tried to make her feel like a woman, and tried to experiment and find out what she liked in bed, cause how could she know? She's been having sex like a man before, and had just discovered why that didn't feel as good as she was taught to believe it should. For most of our relationship I could seduce her in five minutes, and we'd had a very fulfilling sex life, even with her knowing her body is wrong. She even sleeps naked next to me sometimes, knowing I hardly notice that she has a penis, cause I just don't think of her as a man. I assumed she didn't want sex in her last relationship because her previous girlfriend wanted to have heterosexual sex and engage her penis, whereas I honestly would do anything to please her but was relieved she didn't want anything to do with it. But it turns out that she might wind up not wanting sex with me for months and there is no telling when it will be back, and she's telling me it's not because I'm not attractive, but having it switch off like this is confusing, because I thought I was doing everything right and being supportive completely. She says I can go out and find someone else to sleep with but I'm not going to do that, because I love her, and frankly, what having sex with her gives me is not something I can get from anyone else (the romantic connection is more important to me than the thrill of sex itself). It's making me feel unattractive and like she may be falling out of love with me, though she insists that she isn't and I know I have trust issues, so I'm trying to believe her but evidence suggests otherwise.