Well, no, it is not possible. The Government does not control gay people's lives anymore than anyone else. There is an important concept we need to understand. Libertarianism supports the Constitution. Liberalism does not. Libertarians believe that the Constitution is the law of the land. You either adhere to it as written or you amend it. Liberals believe it is a "living document" or that it is not the law of the land only a loose guideline that should not be allowed to interfere with whatever is currently popular.
So, if two people of the same gender wish to get married, they cannot. Marriage is defined as between people of different genders. It does not matter what their sexual orientation is. Two heterosexual people of the same sex cannot get married either. Marriage has a definition and a purpose. No one has to get married. If you do wish to get married you must adhere to the definition.
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