Someones sexual orientation should not make them and does not make them less of a human being. If they are from the United States then they deserve the same rights as any other human being living there. If someone disagrees with gay marriage or just gay individual rights for whatever reason, they should keep it to themselves because it doesn't really affect them unless they chose to let it.
In places like america the constitution specifically states that all people have the right to life, liberty and to the pursuit of happiness. The overall nation is very acceptable of who they let in but they tolerate it and they are trying to get rid of it yet again just like they tried with the African American rights and women's rights. This should be enough for people to just accept it but they won't.
Name a right that straight people have that gay people don't? Even gay marriage is now legal throughout the west, is it not?
You can't force churches to act against their beliefs, but if you are going against the beliefs of that church, that you aren't really adhering to what you need to to be part of that church. But that is a church sticking to its dogma, not a violation of a person's rights.