You say that homosexuality is a choice
For me there is a dilemma here. An emotional response to someone, sexual or otherwise, is part of how we show intimacy.
For some people this attraction is so linked to sexual ideas or emotions, intimacy or understanding someone, becomes sexual when it may not be at all. I have seen people who where very attractive, they pressed certain relationship buttons.
I suspect until you can understand this tenderness, this feeling for another, is just that. If you are very isolated, and find the other sex to other, relating to people of your own sex is a lot easier and in someways safer.
What I discovered is I can care for people of either sex, but it does not mean I want a sexual interaction at all. I have had inappropriate responses from both, but this is more about this kind of confusion than gay or straight dispositions.
If a person can have sexual relations with either sex, it does come down to choice, because there is a point where they are choosing what is acceptable to them. Sex is an act, it is fundamentally about family and children, bonding to form the base of a caring couple to shelter and protect the new person coming into the world. The further we are not coping, the more sexual drive becomes all consuming selfish activity of desire and explosion of need.
Just look at the gay community. It is often sexuality gone mad, extreme expressions, over indulgence, an idea that an act defines your whole personality, which is just wrong, you are who you are irrespective of orientation. In reality we spend most of our lives celibate, coping with what life throws at us, and not wondering about who we are.