I dont see how. Its not about marriage. Its about sex. You only have sex with one person ever.
What? One person ever? Sexual compatibility is a necessity for a successful marriage and people/place/things do change, as evidenced in mine and many other marriages.
These aren't the days of just fucking to make lots of kids to work the family land holdings. We've moved beyong tribalism... Well, actually, no we haven't.
But still, what is the purpose of sexual purity? Awkward painful sex?