But that's the point. You want to be happy with yourself. And yourself isn't the sum total of your physical attributes. It's also your thoughts, feeling, hopes, dreams, fears, worries... everything else that makes you who you are.
Physical appearance is only one little part of that. And if you think like a girl, feel like a girl and know that in every other way you are a girl, then you're not a fraud at all.
The fraudulent aspect would come if you pushed all that away and tried to deny who you are, because then you would be lying to yourself. And, when all's said and done, that's the only person you can't lie to... or at least get away with it when you try.
*hugs*
You were born a girl... just not physically. In every other way, you aren't any different. I don't think a smack upside the head will do so much as giving you a bit of belief and confidence in yourself. How far you take it is up to you, Nathan, but you don't need to convince the outside world that you're female if you already know in your heart that you are. The only person you have to do this for is yourself. Once you're happy and more confident in yourself, that'll permeate through into everything you do.