"sanctity?" We're possibly now intruding into the religious realm, since I can find no defintional notions that at all remove, rather than reinforce religious involvement with the term? 😉 OK then. Perhaps you should address that question to any Muslims you might know...An idea that's seriously and not whimsically offered here. For that matter; you could also inquire as their notions concerning the sanctity of gay marriage as well....Just sayin'...
With "sanctity": You might want to simply uphold Hindu notions instead, but then again, there's this troublesome notion: "Wife and husband are the two wheels of the life chariot." While we're busying ourselves completely redefining Marriage, maybe we should also greatly expand (or simply eliminate) all existent definitions of "Wife and husband" as well, one must suppose...?"