History
While the modern "culture war" may make it seem like homosexuality is a 20th century product that grew in acceptance during the mid-to-late 1900's, the reality is that our history is filled with homosexual behavior. Heck, the Spartan troops of ancient Greece were said to have been encouraged to get it on in a homo-centric way so as to strengthen the bonds within their ranks!
The variable that has mostly caused these modern day debates about homosexuality's "worth"? Religion. Plain and simple. The debate has always been one of "this thing exists" vs. "this thing SHOULDN'T exist, according to my own personal faith beliefs." The "homosexuality is natural" side has always been one that culls data from the human behavior that springs up naturally, and the "unnatural" camp has pretty much always been one pulls its condemnations from the spiritual realm and then works to mold actuality in a way that jibes with their religious beliefs. This was of course true when the Abrahamic religions punished "crimes against nature" in brutal ways, but it's also true when the modern day culture warriors work to shape modern debate with their thoroughly unscientific "ex-gay" programs.
A strongly religious person who believes with all certainty that homosexuality is a sin has every right to hold such a position. However, when rationally looking at this subject, we must chart the historical course of homosexuality along its verifiable place within the spectrum of normalcy, and chart the course of its opposition along its verifiable place within the realm of religion. And when answering questions of science, we should give consideration to the latter while looking at the former, since it gives us much insight into this debate. But it's imperative that we separate the religious convictions, no matter how fully embraced, from the objective research.

You make a critical flaw in this argument. A great many societies, and individuals, disapprove of homosexuality with absolutely no basis in religion . A historical analysis will prove your conclusion quite utterly wrong.
I completely agree, however, that scientific data must stand on its own and have no taint of belief in it (on either side).
The fact of the matter is that a historical analysis will be able to show that societies of nearly every conceivable belief system have existed. Societies have practiced, promoted or at least tolerated polyandry, cuckoldry, polygamy and many other things we disapprove of for many reasons other than religious; "we" meaning a western-European society.
I'm sorry but history does not help your position.
I like your non confrontational approach and your willingness to accept that people have the right to believe differently than you.
Believe contrarily all you like. I shall always take issue with the attempt to wield the coercive power of government to inflict defective reasoning on the citizenry.
I have a Libertarian attitude about Government but it goes beyond "defective" reasoning which is in the eye of the beholder. One person's defective reasoning is another person's logic. Also the comment I made about wasted energy shipping bottled water was "tongue in cheek" because the people who drink bottled water tend to have a Liberal mind set.