Same-Sex Marriage Amendments

It's all the rage now to amend state constitutions--and maybe the federal constitution, too--to define marriage as a relationship between one man and one woman and no other relationship gets the same benefits. That, we are told, is the way to stay true to the country's Christian roots. What the religious fanatics promoting these amendments overlook is the serious risk to separation of church and state.
I'm (nominally) an Episcopalian. My church, through its orderly processes, has ordained gays, and I believe there's a liturgy for the blessing of same-sex unions that can be used at local option. There are other churches that have such rites. I don't want the government--any level--stepping in to tell any religious body who can receive the benefits of its blessings. A government doing so would materially infringe on the barrier between church and state. The state, as Sir Thomas More says in A Man for All Seasons, "hath not the competency to do it." That is, the state can't possibly put together a law that adequately respect the beliefs of all of the churches. If it could, it couldn't possibly enforce the law equitably.
The question for the religious fanatics, then, is this: are you so eager to deprive people in committed same sex unions of their civil rights that you are willing to open the door for government to tell your church what and whom it may and may not bless? Let's take marriage--a sacrament or a blessing administered by a religious body--out of this debate unless we acknowledge that the import of these proposed amendments is to take as much from religious bodies as it takes from homosexuals.