That sounds EXACTLY what I used to be like. While I'm only a year older than you, I felt that way from puberty on. As I became more mature, I developed emotional attraction to guys as well, and now have an amazing boyfriend. I think alot of it is the stigma of being gay, and a sort of "Of course I'm not gay!" reaction. Not knwoing you, I can't tell you if you're gay or not but seeing as how I am and your story sounds similar to mine, I can guess you are.