Mate you are one of a minority that still doesn't accept that people are gay through no choice of there own.
Some people are naturally smarter than others and some people are fortunate to be more attractive than others, it's not a choice.
You have some men that are more feminine in appearance and behaviour and some women that are more masculine in appearance and behaviour, again it's not a choice but that it's self hints at why biologically a person may have the reproductive organs of one gender but mentally and emotionally don't associate them selves with that gender.
People are individuals in so many diverse ways, you just have to accept that
