There is no title/word that can be used to describe the behavior of parents that end up estranged. If the word 'Narcissistic' is used, it is thrown off, "because it can only be diagnosed by a professional". Which I happen to believe is untrue. If I see someone with an arm bent in a place that doesn't have a joint and the person is in extreme discomfort, I may not be a Doctor, but I will say, "It looks like you have a broken arm."
If the word 'Toxic' is used, it's just plain "cruel" and what does "being toxic" even mean?
If the word 'Abusive' is used? Who is a child to decide if they were abused...
So I will throw out the word 'Clueless' as a possible choice.
In my experience, the parents who end up estranged are 'clueless' as to how their behavior affects those around them. Whether they are "willfully clueless" is a matter of debate.
www.psychologytoday.com/ca/blog/matter-personality/201411/parents-cut-adult-children-clueless
Lasr two letters continued Jan 24
Angela Rayner lashes out and calls Sunak “pint sized loser”.