1) becoming self absorbed/narcissistic is a hallmark of MLC, so definitely try to separate that part. There are narcissists who have MLC and there are MLCers who become narcissists.
2) being a narcissist is not the same as a personality disorder. Reason I say this is that someone who is a narcissist may let that go through therapy and healing one day, but someone who has narcissistic personality the same) can not be “cured,” but they are pretty easy to spot.
