Here's an interesting explanation of what happens when bigotry becomes so heated that the thought of anyone even pretending to enjoy the same rights as the majority drives the bigots to amend constitutions with the legal equivalent of a cannon blast blowing out the candles of a birthday cake:

The proposed amendment defines marriage as a union between a man and a woman. But, just to make doubly sure that no clever judge reads anything like gay marriage into Virginia’s constitution, it withholds recognition of “a legal status for relationships of unmarried individuals that intends to approximate the design, qualities, significance, or effects of marriage” and prohibits the creation of marriage-like arrangements for non-marital relationships.
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Except that -- as same-sex marriage opponents are often the first to point out -- gay couples can already obtain many of the benefits of marriage through wills, trusts and contracts. Last year, Ramesh Ponnuru argued in a National Review cover story that making the incidents of marriage even more widely available to people living in other arrangements might point the way to a compromise, or at least lower the temperature of the debate. The Virginia amendment, however, is at least open to being interpreted as cutting the opposite way, complicating private contracts between same-sex couples that aim to approximate marriage and perhaps even making such contracts that already exist unenforceable.
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Such arrangements aren’t limited to same-sex couples. Unmarried heterosexuals, family members and even roommates might work out hospital visitation rights and power of attorney in some jurisdictions. Under the amendment, what would happen if they came to Virginia? “A physician may choose not to honor the contract or feel that the law prohibits him honoring the contract,” says Kent Willis of the Virginia ACLU.

Something along the lines of "Marriage shall only consist of one man and one woman," as hateful and wrong as it is, would've been too restrictive on the folks trying to save the soul of every Virginian. Every day I creep closer to the thought that every Constitution in America should be rewritten to explicitly state that rights are granted by the majority, and are never unalienable. Maybe we can come up with constitutions designed like Mad Libs. The blanks could have multiple choice answers, with the list of possible answers agreed upon by legislatures and submitted to the masses every November to perpetually certify the will of the people. It might be horribly inefficient, and counter the principles upon which America was founded, but at least we'd have a much easier time saving society every time some new threat (a derivative of the Homosexual Agenda®, no doubt) appears. It could work.