If you’ve already tried the path of dialogue with them and you’ve already invested your time in trying to make them aware of their behavior and how deleterious it is and it hasn’t worked, then distance yourself from them before they ruin your life. Detaching yourself from them, especially in the case of people with strong narcissistic tendencies, is the most suitable solution; ignore them as much as you can and keep going on with your life.
Depending on your soul level, you can also support yourself with runic magic to block their influence and cut any spiritual ties you may have with them. If you don’t block this influence, you will be held in shores that will not allow you to grow, because you’ll stay trapped in the effort of trying to deal with them. Also do not feel guilty about acting in your best interest here.