Shall I assume, by your question, you consider heterosexual persons perverted? Take a good look at the rest of the animal and some of the plant kingdoms and see how many other species pervert sexual contact as homo's do.
Correction: you don't choose to be male or female. You are born either male or female, and sexual attraction to the opposite sex is powerful congruent natural consequence of that fact.
To engage in homosexual behavior, you must choose and act to override that powerful and congruent sexuality that is the birthright of males and females.
The fact that in most gay and lesbian relationships one partner typically adopts an aggressive "male" role and the other adopts a more passive "female" role is further evidence that the male-female complementariness is strongly in-born.
In sum, you do not "choose" to be heterosexual--it is natural and congruent consequence of male-ness and female-ness. You choose to be homosexual as an unnatural and incongruent behavior set.