The narcissist is a pendulum who decides to swing to extremes when they want to. They confuse their supply when they are centered in the middle (normal state, sweet cycle).
Their intent is to relax a person's state of mind without thinking it has to go into high gear in the flight or fight mode. But when the narcissist sees that being in the center has accomplished emotional and mental sedation in their supply they begin swinging to extremes like a pendulum.
This is what alarms most empaths because normal is in the center, balanced such as in balanced weights on a scale... not swinging pendulums out of control. Empaths have a hard time fathoming the reality of it all because their are wired to be loving people, stable, consistent. Their hope is that the narcissist will again come back in the center where there is peace, quiet and normality. This expectation is what takes the empath on a roller coaster ride because when you put your expectations on the narcissist you will never get off the roller coaster unless they bring it back to ground 0.
This is once again manipulation and mind control for the purpose of bringing you back to the center of the pendulum so they can swing to extremes once again.
I picture the narc's supply sitting on the pendulum swinging back and forth screaming stop, stop! Then the pendulum stops after the dramatic event and the empath forgets, denies it all happened or confronts the narcissist to stop their behavior. That would be like telling a lion to stop roaring, a snake to stop slithering on the ground, a shark to stop searching for blood.