Not without some form of mediation by a judge that ensures that the interests of both sides are protected. Texas walked out and left responsibility for debt and national obligations to the remaining states, and with every piece of federal property it could get its hands on. If you want to carry on the marriage analogy then I imagine that would constitute abandonment and various forms of theft.
Fair point. TX could claim a per-capita share of the national debt and full ownership of (formerly) federal property within state boundaries, and they could give the Feds the option of attempting to force them to stay but charging all war costs against the TX share of the national debt if there is a war and (as is likely based on relative motivation) TX wins. I don't think Obama has the guts to initiate a war, not even against Americans, even though he doesn't identify with us.