1 man and one woman is only half of the true definition. One man and one woman until death do them part: no divorce. That should be the next hurdle in the Defense of Marriage movement.
The divorce rate is abhorrent, but the thought of the government being able to force two people to stay together is just as bad. There will always be circumstances where divorce is, in fact, necessary (like when the relationship turns legitimately abusive and dangerous for one or both partners).
I think resisting pushes to make marriage about short-term personal satisfaction and validation (e.g. same-sex “marriage”) is a big step in restoring the culture’s reverence toward marriage.