riven_one, and Jaimey, I think, have hit the nail on the head.
I don't recall seeing any of these things in libraries (even the ones I worked at) as a kid, even though "Annie on My Mind" was published in 1982, 4 years before I began working in a library. And, the escapism in fiction allows for the "vicarious experience," as my high school English teachers would have described it.
Yochanan, I did know teenagers who were aware of who and/or what they were as they were developing. These were few folks, to be sure, but they were there. I even remembering asking one of my friends when she figured out she was gay. She said, "I was born gay." She pretty much realized it all along even if she didn't necessarily had the vocabulary to describe it when she was young.
So, I think that some folks are able to discover truths about themselves when they are still youngish. I just wasn't one of them. Or, what I should say, I had in a way figured it out but didn't really accept it because...
1. those things happen to other people, and I was just a "normal" guy
2. I was born a boy so I would just have to deal with it (binary illusion)
3. I didn't have the vocabulary to describe how I felt
4. I didn't have the support to be me (suburban Catholic upbringing)