This is infinitely simple : What is the government trying to do by having any kind of marriage status ? All the government needs to know, on any level be it federal, state or local, is if in terms of finical activity, you are acting as a single person or not.
The government should remove itself from the discussion of sexuality in terms of marriage because it is irrelevant to the government. Instead the only thing that needs to be known is if you are acting as a single person or jointly with another person. Marriage would qualify for joint legal status, as would civil unions, and civil unions should be accessible to everyone who wants to file for them. Through the legal status of civil union the government can get out of the way of the religious bigots who want to complain about the sanctity of marriage and the government can get on with handling the legal issues of people who are acting in their lives in a joint financial status for whatever damned reason they want to.
Gay or not, it doesn't matter. Right or wrong, it doesn't matter. The point is how to legally handle a couple of people who want to act jointly in a financial capacity.