Hi!!
Don't fret, actually, your story is nearly identical to mine. It's kind of scary!! Haha.
The whole "man dude" thing with straight guys and how they treat women, it's exactly how I feel, too. I guess the way I judge it is if you are okay with dressing in women's clothes for fun but being a man at all other times, it's not transsexuality. But, that doesn't seem to be the case.
People have recommended to me what I'm going to recommend you should do--see a gender therapist! I have an appointment - my first - in a few weeks and I'm scared, but it's the only way to help sort out all the hooplah going on in your head ya know?
Good luck! You'd make a great girl!