I don't see that as a government problem, it's a state problem. For example, if the government outlaws the use of marijuana and you go ahead and use it, you can obtain every benefit your state allows. But, under federal law, if you violate that law, you can't ask the government to protect you since you knowingly are violating federal law.
I think this whole gay issue is the same. If a state says that you can legally marry your same-sex partner, that's within the authority of that state to do so. But that state authority doesn't necessarily place any burden on the federal government UNLESS the federal government is willing to allow those states to include federal benefits among the same-sex marriage.
As far as I am concerned, marriage remains a state between John and Mary, NOT John and Larry or Joan and Mary. This whole issue affects ~3% - 4% of the population and doesn't deserve all this media hand-wringing. We don't see anything like this when it concerns conservative issues or Constitutional rights (such as the Second Amendment that the left anbhors!), so why are we wasting so much oxygen to appease a clear minority or the population!?? It doesn't make sense. Tell'em to go back in the closet, I'm tired of them being in my face nd in my business.
But that state authority doesn't necessarily place any burden on the federal government UNLESS the federal government is willing to allow those states to include federal benefits among the same-sex marriage.
This is exactly why the federal government must define marriage. It was the impetus behind DOMA.