It's also possible to argue that it's natural. I had a homosexual dog. That's all I'm saying about that, but homosexual behavior in nature has been documented.
Just because some animals have homosexual tendencies doesn't make those tendencies natural. Your argument suggests that any abnormality found in animals, no matter how useless or harmful it is, is "natural" and that therefore there is nothing wrong with it.
That's funny, because, ya know, if it were unnatural, why do people and other organisms display homosexual behavior even if it can't result in reproduction?
Just because things are being used for reasons they weren't "intended" for doesn't automatically make them wrong. Homosexuality is just a slightly more extreme than usual example of this.
So you think that no mental illnesses are "unnatural", then? People certainly display those, and animals do too (like dogs with apparently hereditary aggression problems; my family recently had one like that, I think).
I don't know if you read the later parts of the article, after the "homosexuality is unnatural" section, but there are plenty of reasons to consider homosexuality a bad thing. Just look at the statistics lower down.
Not everything used for reasons it wasn't intended for is wrong, but the area of human sexuality is different from other areas, since the natural purpose of sex is to create new human life. Therefore, it is a far more important matter than, say, what tools should be used for what purposes in fixing a car. But of course, if you don't consider human life sacred, I don't know if I can argue this with you.
Sorry to hear about that, neotev.
