For one, the statistic is "men who have sex with men are nearly 20 times more likely to be infected with HIV than general populations" in the world, not just the US. And "20 times more likely" is not 20%, it is 20 times the percentage of the general population risk (which is about the difference between receptive vaginal and receptive anal sex here: http://www.thebodypro.com/content/68672/putting-a-number-on-it-the-risk-from-an-exposure-t.html ).
I have also condemned promiscuity, which increases anyone's risk through shear number of exposures and is very prevalent among the homosexual population (Many "open" gay marriages: http://www.nytimes.com/2010/01/29/us/29sfmetro.html?_r=0 ). But I have already said that this alone is not the only reason for my opinion.
That's true, you've also claimed that homosexuality is responsible for mental illness and drug use.