As a Christian you have the right to believe homosexuality is a sin and the right to say so publicly. You may also choose to not fellowship with LGBTQ people. What you don’t have a right to do is to prevent those people from having equal treatment by our government or to have access to services that are otherwise publicly available.
Your faith is not our law. Many churches, congregations, faiths and people of no faith accept and support people who practice alternate sexual lifestyles. Your beliefs do not trump the beliefs of others. You do not have a right to call them fags, queers or sodomites any more than you want to be labeled as “missionary position.” How and with whom you have sex is no one else’s business, and theirs is not yours.
You can believe their lifestyle is not honored by your god, you can believe that punishment will pour out on our country for allowing homosexual relationships. But, if your god did not punish us for lynching blacks, killing thousands of innocent civilians as collateral damage in our wars and all the other evil we have done throughout history, what makes you think accepting same sex marriage deserves his anger and retribution?
Whether you accept LGBTQ people or not, they are not going to disappear; they are people and citizens that deserve the same rights as anyone else. Protesting and throwing hissy fits about homosexuals and transgender people having equal rights will annoy you much more than it will bother them.
Poverty, violence, hunger and environmental changes are much bigger threats to our society than a few folks that love each other, even if you do not approve of their relationship. Maybe it is time to focus on things that really matter, heck; we might even be able to work together on some of it.