What is a narcissist trying to get from you when they denigrate, insult, manipulate and provoke you?
The technical term is "narcissistic supply". Narcissistic supply is basically attention. Adoration, flattery, envy, jealousy and admiration are preferred. However, if you catch on to them and start to withdraw narcissistic supply they may lash out in surreal and even bizarre ways. Emotional manipulation is their typical response. They may insult or guilt you. They may play the victim and turn other family members or friends against you, getting them to implore you to "please talk to your mother" or "remember he is your father". If emotional manipulation fails to work they may graduate to more primitive methods. They may hold your belongings hostage or stalk you. They may text you incessantly or utilize Facebook to publicly attack you.
You may be puzzled as to why they think this aggressive behavior will win you back. But you fail to understand what they are after. They don't want love, they want attention. If they can't get positive attention, they will take negative attention. If they can't have your admiration, they will accept your rage. But they must provoke some response from you. That is their goal - to provoke a response, any response. It solidifies, in their minds, their power over you, that they are calling the shots, that you are weak, or gullible, or easily manipulated, or vulnerable or whatever they have labeled you in their mind that means you are "less", less than them.