Familes that are still together

I was telling my kids how rare it is that their parents are still together, and both sets of their grandparents are still together.
Of any of thier friends that i know, either their parents are divorced or at least one set of granparents are have been divorced.
To clariy, married and together, same thing... I do know a lot of people have been together for a long time, but never married.

Is that as rare as I think it is?