While it is true that some individuals have always deviated from the familial pattern (man & women) established by God, it is the only pattern blessed by Him.
It is a great and magnanimous society that tolerates the sinner. That was one of Jesus' points, yet let us not forget His follow-on admonition, "Go and sin no more!". While all of us sin, only a fool promotes sin. What society sanctions, society promotes.
Society has a legitimate interest in promoting the kind of family relationships it thinks are best for society's long term interest. Marriage, then, is a system of laws bundling privileges and responsibly for the promotion of the kind of stable family units that it deems most conducive for nurturing children.
That is why divorce may be made deliberately cumbersome or why states may outlaw plural marriage. Society gets to choose how best to promote it's own future.
If folks want to commune together, they can. IF they want to set up partnerships, joint accounts and mutual living wills and powers of attorney, they can. The law does not interfere. However, if it is to be argued that society has neither interest nor right to promote through its laws human behavior and relationships, then how can any conceivable or inconceivable relationship be disallowed? Why not 2 men and their 3 wives? After all they seem loving and committed! (BTW this is not ridiculous slippery slope logic; such lawsuits are already before the courts)
The constitutional provision of freedom of association does not require a universal and arbitrary approval and promotion. The society of man is not a free-for-all with no limits. Those limits come from God. If we are just electro-chemical reactions, then dog eat dog, blow it all up, Columbine, so-what, its just noise in the cosmos. But there is a God, and He established what is right and what is wrong even if we cant see the meaning in it and that is the only justification for any civility and order we enjoy. This is in no way establishing a religion to acknowledge that our justification for right and wrong, mercy and justice derives from that revealed knowledge.
We must not promote what God has forbidden. We must not send the message to our land that such a massive departure from Gods pattern for families is an acceptable "alternative". It is not.
Steve Marquis