I also think that children have a much clearer picture of their parents than we give them credit for.
I know growing up, I didn't want anyone to know that my parents were my parents especially my dad. I avoided being around him as much as possible from as young as I can remember. While at the same time my mom was full of nothing but excuses for his embarrassing behaviors & couldn't understand why I saw things actually more realistically than she did.
Kids that have never had the emotional attachment don't have a strong attachment to that person unless someone feeds them the expectation that they "should". While parents have built up their individual emotional attachment expections of each other before the child is even born. Seriously, the kids usually have a much clearer picture of a bad family situation than the parents do. Good to listen to their wisdom