Setting aside the apparent need of the Left to destroy civilization, the root cause of the marriage problem is that government is involved in marriages. I propose a simpler solution; namely that a legal agreement be signed using any notary public and presented to the county clerk for registration of the document. The clerk would simply be noting that a legal document had been filed. The couple could, either before or after that point, find a person of their choice to perform whatever religious rights they and the person performing the rights agree to.
The first element would satisfy all government needs for the registration of the relationship in question. The second element would independently satisfy the moral, ethical, and social needs of the couple and the person performing the religious ceremony.
End of drill.