No.
Let this be the catalyst to do what you should have done the moment you split. Cut all ties with the exception of interaction over the baby.
Block him on everything bar one method of contact and only reply on that regarding matters about your child.
I suggest you educate yourself as much as possible on narcissists too. It's good that you know what he is but... it sounds like you havent quite grasped what that truly means yet. Narcissists are empty, all they know how to do is take. In order to take, they sometimes wear a mask of goodness or affection. But you must always remember that they are hollow. With the exception of rage, hate and greed perhaps.
He is not changing at the flip if a coin. There is no good and bad him. Only the bad and the mask.
Distance yourself as much as possible from him. Do not let him fool you again.
And as for his words: they are not reflective of you. They are reflective of him. Of his hate and spite and jealousy.
Protect yourself. And protect your child from him in time, read up on narcissistic parenting and what to expect.
See him for what he is now. And make choices accordingly.