My experience is the much less serious variety, my parents meant well and did what they thought was right at the time but there were definitely issues - excessive punishment by one parent and periodic emotional unavailability owing to the other parent's MI (I still have a lack of connection with that parent).

The excessive punishment was probably not regarded as excessive at that time, that parent now regrets it and has voiced so.

The other parent I have compassion for, the emotional unavailability was beyond her control, the MI was beyond her control. I don't confront her, it would do no good and probably cause further harm to our connection.

I'm a parent, I know I'm not perfect - a lot of my perspective is shaped from that.

Where there has been out and out abuse and harm it is quite different I'd imagine though.