Todd Witteles, the forum owner, is as responsible as "Singer" regarding these kinds of posts. Anyone offended by posts such as these should take it up with Todd, preferably in person. Or, since these posts directly reference family members and such, it might be best to bring it up with Todd's significant other. I can't imagine Todd would allow similar posts to be made regarding his family. But we can always test that hypothesis.
One of the problems with these kinds of posts from "Singer," is that he is simply making stuff up. He presents as if he has access to some kind of private information, but in reality he does not. He's just guessing and putting fictional nonsense out there. If he had any actual details or evidence, it would obviously be included. It's not like he's being judicious. But facts or evidence, he never has either.
Now if I had to "guess," I'd say these kinds of posts originate from someone in the poster's immediate family being gay themselves, and the poster cannot handle it. LOL, how's that for "guessing?" Just as some of the poster's rants about other people being bad drivers probably have something to do with the driving skills of his family members.