Hans- yet again I'm going to wind Naomi up by telling someone they don't understand, but you clearly don't understand the difference between sexuality and gender.
You can be gay, straight or bi sexual without ever desiring to be the opposite sex.
You can desire to be the opposite sex and be either straight, bi or gay.
Your desire to be a gender contrary to the one you were born does not depend upon your sexuality.
With regard to myself, both my (male) partner and I are bisexual, but we could both be straight or only one of us bi, or indeed be living with one gay partner and one straight or bi partner in a marriage because sex isn't everything.
People are very diverse and assumptions do no-one any favours by and large, but the main point of my post is that sexuality does not equal a desire to change genders, so neither my partner, nor I am confused at all about our gender, I'm a girl and he's a man and we identify as such.