Here is a long quote from Gagnon’s book, The Bible and Homosexual Practice pg 424-5 about the idea that homosexuals cannot change:
“If you press them (those that believe that homosexuality is immutable) they will say that it is obvious that homosexuals are “born that way”, implying some sort of genetic or hormonal determinism. In effect, such critics must completely reject environmental influences, even though the consensus in the scientific community–even among homosexual researchers such as Hamer and LeVay–is that environmental and psychological factors still play a significant role in the development of homosexuality. They must ignore the identical twin studies which have conclusively demonstrated that genetic influence is at best small and, in any case, certainly not immutable. They must ignore cross-cultural comparisons which show incredible malleability in rates and forms of homosexuality, not to mention intra-culteral comparisons such as he effect of urban settings, education, income and religion on the incidence of homosexuality. They must discount the capacity of rearing to override the genetic gender of people born with ambiguous genitalia. Indeed they must reject out of hand all the psychological and psychoanalytic data we have about the enormous effect that parental upbringing and peer socialization has on sexual development of children generally (not just homosexual development). they must too countless studies on behavioral modification. …etc.”
His whole chapter, The Hermeneutical Relevance of the Biblical Witness gives a great deal of info on this matter.
So, it is not that I think that it is merely a choice people make. There are profound influences. But deciding what to do with one’s proclivities is among them.