You sound like a kind and forgiving person. But I refuse to believe there is "nothing evil" about parents engaging in "massive screamfests" that cause their small children to huddle together and pee the bed. And when we shrug off or rationalize the wrong that others do to us, we too often end up repeating the behavior in our own lives. That's what so often happens with many of the children of divorce: (stage one) I'm mad that dad had an affair; (stage two) now that I'm married myself, I understand why dad had that affair; (stage three) I really need to have an affair.
I certainly don't shrug off their behavior. I've always let them know how much that tore us up and how wrong it was for them to put us thru it. I've known them all my life, they are not evil and never intentionally hurt us.
We are all flawed humans, their flaws were in dealing with conflicts. They tried to out yell each other to be heard. One day they were teenagers the next they were parents raising kids and fighting wars. It happens, I can accept their failings without putting the devil in them.