I'll start with your first point "Just because someone has a disease it doesn't mean they have a bad lifestyle.". I consider alcoholism to be a disease. Do you? Nobody becomes an alcoholic with a good lifestyle. Most diseases start because the person does something wrong, they drink too much, eat too much. Gluttony is a sin, God warned us about it. If you look at all the major diseases, God warned us about each of them in a general way. God might not have said "don't gamble", but he did say avarice is a sin. Each time humans rebel against what God has told us, we suffer for it. AIDS is no different.
Your second point "Just because you classify homosexuality as a disease it doesn't mean its right or wrong or normal or abnormal.". Homosexuality is wrong, almost every religion teaches that. Those who practice it are doing wrong. God punishes some of them with AIDS, and now a new strain of AIDS. What do these people need to get the message, to have San Francisco sink into the ocean because of an earthquake? I don't think it was random that New Orleans, aka Sin City, was struck.
Your third point "The fact is, love is a biochemical phenomenon, and I'm sure gay couples experience the same type of love that male-female couples do.". Gays do not experience the same type of love that heterosexual people do. Read some research journals. Homosexuals tend to be very promiscuous, they have hundreds of sex partners, where normal heterosexuals don't. In one way, I guess you could classify homosexuals are suffering from a sexual addiction. But it is worse for them, because they don't even know the right sex from the wrong sex. Something in the thinking of a homosexual is fried and does not work normal. It is like an alcoholic who won't stop drinking. They can do it, but the don't.
Why does God target some for disease and not others? I think part of the reason is the person doing the wrong must have full knowledge they are doing wrong. When people like you act as an enabler, you are not doing anyone a favor. You are causing harm. One day, people will say that pedophilia is okay. Will you be one of those people who says "Oh, pedophiles love the same way. You're a bigot for not letting pedophiles live how they want".