Marriage seems to be humanity's way of getting people to be responsible for their "significant other" and offspring, WAWYM.
Marriage seems at its core to be a way to sort out"who's watching the kids" as FHN said.
Being a fatherless child was a problem w/o government subsidies.
Being "used" then discarded w/o ceremony has indeed a problem for women.
Jesus seems to be concerned about failing to truly acknowledge responsible family connection:"Corban"let children ignore the welfare of an aged parent. The woman at the well had not made a claim to a husband but was yet "shopping" herself around--no mention of children.
I don't know what to think of marriage these days. I mean that.