The narcissist may be gone, but they live on inside of you. Because of the enmeshment, brainwashing, entrainment, intermittent reinforcement, parentification, and more manipulative and predatory techniques, you are poisoned. You are filled with introjects (the narcissist's voice), ruminations, peptide addiction dopamine cravings, trauma bonding and the list goes on!
This explains in part why recovery from such a relationship is so difficult and unlike any other!