Consider the possibility that, just as humans come in many different shapes, sizes, and colors, we also come with different sexual orientations. Most of the people on this planet are straight, but some are gay/lesbian, and a few others--whether straight or gay now--may very well be bisexual. Individual people are different from one another, and we ourselves are not exactly the same people we were 10 years ago, one year ago, or even yesterday. Very little--if anything--in this world is absolutely constant; we and everything around us are always changing. I believe that those who claim "I'm not gay anymore" are either denying an essential part of themselves because of great shame and/or frustration, or that they are inherently bisexual and have simply grown into a different phase of the lives that God intended for them from the very beginning.
I've had friends of many different sexual orientations since I was a young teenager, (more than 22 years ago) and I have to emphasize the fact that none of my gay/lesbian friends WANTS to live in some sort of spotlight, be rejected by their families, or treated differently. I am a college-educated, active church member who understands that the Bible has been re-translated, edtited, and re-written many, many times to suit whomever was/is in power at the time, and I also realize that no single religion on this planet has an exclusive hold on the "truth."
My gay and lesbian friends are intellilgent, law-abiding, tax-paying people who are devoted to their non-dysfunctional, non-abusive families. They pay their bills, they get stuck in traffic, they look forward to vacations, and they worry about our nation's future the same as nearly anyone else you may know. They are supportive friends, hard-working employees, loving (and, yes, monogamous!) partners, and even responsible parents. (Several gay/lesbian couples I know have adopted hard-to-place children whom so many other straight "Christians" wouldn't even consider taking into their homes and their hearts. As a professional educator, I can vouch for these couples' solid parenting skills and their childrens' mentally, spiritually, and emotionally healthy development)
The freaky images and stories that so many homophobic Americans cannot erase from their minds are merely sterotypes that get plenty of air time because they are (to some) shocking, controversial, and intriguing--BUT THEY ARE NOT ACCURATE DEPICTIONS OF MOST GAY/LESBIAN/BISEXUAL PEOPLES' LIVES. If you don't want to be a part of the gay/lesbian community, fine--but don't fool yourself into thinking that you don't know any gays, lesbians, or bisexuals at all.
To me and many of my friends, straight people preaching vehemently against homosexuality sound about as relevant as those in the dark ages who insisted that the Earth was the center of our universe...because that's "what the Bible said." Think about it.