The narcissist Know-it-all seems to have all the answers for everyone else. They act as thought their opinions are facts and that anyone who thinks differently from them is simply wrong, stupid, inferior, or worse, and disagreeing with them is seen as an attack .
Evening explains the one and only reason that your abuser hates you is because you confront their false reality, and to them that feels like you are a threat to their very lives. They will fight you to the death without any regard for you as their child, spouse, friend,sibling, etc. They have no problem with it if you lie to them so long as you don't confront them, so authenticity has almost no place in the role of a narcissist.