Government control and regulation of marriage is the right of the slave owner to regulate the procreation of owned slaves, just as a cattle farmer has a right to determine which bull services which cow.
Any adult man (male or female) who uses and is identified by the legal identity name owned by the State is of 'slave status' as far as the State or UNITED STATES is concerned. The American people have been made slaves by the unauthorized use of the State owned name with which they have learned from childhood to identify themselves. The 13th Amendment of the US Constitution makes the Government's imposition of involuntary servitude constitutionally legal, as Government is an incorporated body , and thus a make-believe ship at sea, under maritime law where an accused is guilty unless proven innocent.
Free will adult people do not need Government permission to live together, and play with each other's body in privacy, if they wish to do so. Only the negative form of the Golden Rule imposes any moral restrictions on an adult human relationship.