Eeeeesh.
First off, the term "gender identity" is being used incorrectly here. Gender identity refers to one's own sense of being male or female, in the psychological sense, as opposed to the physical. It was originally used in reference to gender reassignment surgery.
It is not the same as "sexual orientation," which is the term i think most people posting in this thread mean to use. Sexual orientation refers to one's preference of sex partner.
It is simply not true that all or most lesbian women feel themselves to be or want in any way to be male, nor that gay men feel themselves to be psychologically or emotionally female/want to be female.
Another unspoken notion muddying the waters here is that of "gender roles," defined as a set of culturally-defined behavioral norms associated particularly with males or females. Religion has a lot to say about this, obviously.
Homosexuality challenges heteronormativity simply by virtue of same-sex attraction. The degree to which a gay person conforms to or defies other gender role expectations, whether out in the social marketplace or within the privacy of the bedroom, is highly individual.
Modern psychology proposes that sexual orientation is a product of both nature and nurture, and that our sexuality is pretty well formed by the age of three years old, at most five. Gays don't "choose" to be gay any more than straight people "choose" to be heterosexual.
And, finally....lots of gay couples have babies, folks. They make their own, and they also adopt children that straight people put up for adoption. Doesn't anyone else here watch The L Word?
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