I think it is helpful to think of gender identity as a continuum with extremely male and extremely female on each end. Most of us find that we fit in somewhere in between. Dr Cerise Richards spoke about the transgender continuum during her keynote speech at the 2010 Fantasia Fair: http://web.me.com/ceriserichards/TRANSGENDER_CONTINUUM/FANTASIA_FAIR_KEYNOTE.html
We're all unique and have to determine where we fit in on the transgender continuum. An experienced therapist can help with this.