[iRyan]

There is also a distinguished difference between gender and sex. Gender is psychological, sex is physically biological. Biologically speaking, you are born either male, female, or intersex. But psychologically, you can identify your gender in a way that may not fit with the societal traits associated with your birth-sex. It can be so intense, that you literally feel as though you were born in the wrong body. But really, all gender identity is a social construct. It can certainly exist as almost exclusively masculine, or exclusively feminine - but there's the entire spectrum in between as well that every individual falls differently upon.

Male (+masculinity) and female (+femininity) is what we typically associate with gender, but personally, I believe gender cannot truly be defined in only these two terms - but it's a very simple construct that society and language has imposed upon us and we all play along.

I think that transgender people do not feel comfortable in their birth-sex due to the societal expectations associated with it that do not resonate with them at all mentally or emotionally. And society will only accept them as one or the other, to be ambiguous or 'impassable' puts them at a greater risk of unsafety.