I was about 13 or 14, I think I have posted this before.
I had just cleaned up the house and when my dad came home he said to me, "Damn son, your going to make somebody a great little wife."
I laughed it off, went to my room, and cried for hours. It was then and there that I absolutely knew for sure, 100%. I don't know why that did it, I don't understand why some stupid little jab made me realize it, but, it did. Instead of saying what I wanted to, I decided to run away, being fairly intelligent and knowing that I probably couldn't make it on my own. I told them I wanted to go to Military School. I worked my butt off to earn a scholarship, and I did just that. I had hoped that Military School would change me. Then later, I went in to the Military with the same hope.
Only my solution is a bit different. While I know it and while I accept this about myself, I REFUSE to do anything about it, and I REFUSE to accept the current solutions to this problem. It's hillarious if it wasn't so real. I hate who I am (Physically), I hate the idea of changing (Because of the social ramifications of it, fear, etc...), I hate the idea of staying the same (Because I am miserable). So, for me, if it comes to it, I'll go down with this ship, and if the storm gets bad enough, I have no problem sinking the boat.
So, yes, that was my defining moment of self-realization.