In the United States there is both civil marriage (marriage licenses obtained from a clerk/ Justice of the Peace’s office) and religious marriages performed in your church/mosque/synagogue etc. A civil marriage is what has weight in entitling you to federal and state benefits while a religious marriage is more ceremonial and is what shows you as a couple before the eyes of God.

Some religious groups will preform marriages on homosexuals, others will not. Such marriages do not have federal standing and religious institutions are not required to marry anybody they don’t want to. (Separation of Church and State)

In the United States same sex marriages are legal in both Massachusetts and Connecticut. (They were also legal in California until Proposition 8 passed, which overturned the previous Court ruling that had made the marriages legal.) Additionally, while New York, Rhode Island and New Mexico will not perform these marriages, they recognize those performed out of state.

Oregon, New Hampshire, Vermont Hawaii, Maryland, Washington, Maine, and now California perform civil unions that give most of if not all, depending on the state, the rights of marriage.

Hope that helps explain things! :)