It gets messier when the Federal government recognizes these things called “marriage.” The IRS will not bless a live-in relationship as a marriage if a state does not. (And how do people in D.C. get married, anyhow? Do they have to look to Maryland or Virginia law?)
Aye, just as it gets messy when the federal government recognizes any religious ceremony (e.g. baptism). It was always a mistake for the federal government to get involved in marriage, certainly the 1st Amendment prohibits it outright.