It's not like changing underwear. Imagine trying to change a heterosexual into an exclusive homosexual and getting him to be attracted to the same sex. In effect doing the opposite to a homosexual is probably even more difficult but not necessarily impossible.
It's not an easy thing to change like that. My heart goes out to homosexuals who want to stop. Those people should be given the highest compassion and patience.
To encourage them that it's ok to live that lifestyle is the least compassionate thing a person can do to them. I think that if not giving that option more of them would at least want to try and stop the behavior.
There was a guy I used to go to the shooting range with and I found out he was gay, I asked him why he followed that lifestyle and he said that he grew up a Christian and dated women and was attracted to women but was emotional similar to a women. When he went through several breakups, he started dating guys and admitted he wasn't born gay that it was a lifestyle change.
I highly doubt homosexuality is something someone is "born" with, I think there are other factors that influence it like metrosexual lifestyle or if someone is doing something they aren't supposed to (like a boy playing with barbie dolls) and the parents don't tell him it's wrong, they believe there is nothing wrong with those feelings and nothing suppresses it.
Think of it like this, how many kids used to step on bugs or would use those magnifying glasses to burn insects because they thought it was funny? Kids don't know right from wrong so if they grow up with that mentality, is it any surprise that this would explain how homosexuality is tolerated and why men are dating other men?
It is immoral and a sin, there's no need to sugarcoat it.
Obviously there's reasons people become gay, the problem is society today tolerates it and gives them justification that what they are doing is right.