Ok, I did it! I told him. Cop out warning: I did it via e-mail. Yeah, I know! I would have done it in person, but he's on vacation and will be for the next week, and I didn't feel like I could wait anymore.
This is actually a strange tradition of ours, though. Like I said, I'm terrible at having personal conversations in person. It's really like trying to talk to a five year-old about Calculus. You'll get a lot of silence, and even if they tell you something, it may not make any sense. I'm more of the quiet academic type, so I'm much better at articulating myself in written form. There have actually been a few times in our relationship where we've been dealing with some tough issue, and writing it out was the only way I could really express myself. It's certainly not a substitute for conversation, but for us, it's a useful tool to break through the awkwardness and fear and actually getting conversations started.
On another note, I never really thought about it until now, but it makes sense that he would know. For most of my life, I saw exploring this part of myself as a vulnerability that my family would exploit, so I simply didn't. With him, I feel free. I never talked about it, but I didn't really try to hide it or act like somebody else. So I guess if this thing is real, which I'm pretty sure it is now, it would show, wouldn't it? How would he not know, if it was really part of me, and I wasn't trying to hide it?
Edit regarding his reply: I talked to him on the phone a few hours later, after he read what I sent him. As I expected, he told me knew most of what I said already, and that he was proud of me for actually coming out and saying it. I feel like I'm really lucky, in some ways. I can't really go to my family, as I have a poor relationship with them. But it's good to have at least one person who understands you and cares about you.