No, it isn't the only thing that God calls an abomination, or that those who love the Lord receive from Him as authority, since He would know, since He is the judge and has the power of life and death in His hands.
But Homosexuality IS the topic of this thread. So, we do have to do our best to stay on topic.
But the reason that homosexuals run into trouble with Christians, politically is that homosexuality is the only one of those things, that God finds abominable that are politically trying to force down the throats of all of society that the practice is normal when it is indeed perverse and abominable and try to force us to allow them to teach our children in schools that gay is okay and flaunt their sexual deviation in public in front of our kids at family places, such as theme parks etc.
What you do in your bedroom is your own business, and between you, the person you are with and God. (can't escape God's part).
When you bring it out of the bedroom, and into the public arena, that is when it becomes the rest of the world's business.