That's where state nullification comes in. Where there is a genuine controversy about a federal law being constitutional, the state must make a good-faith effort to read the text in the original understanding and intent.
Here with marriage, it should not be a close call. The state could nullify pending a possible attempt to have the feds reconsider the act and repeal it themselves.
At this point the most important thing is to get state involved in this valid, constitutional process.
And what state might refuse to submit to an unjust Fed. ruling?