Denial in mentally healthy people quickly evolves into rage. There are a few types of rage. It can be focussed and directed at the narcissist, at other facilitators of the loss such as the narcissist's lover, or at specific circumstances. It can be directed at oneself which often leads to depression, suicidal ideation, self-mutilation and, in some cases, suicide. Such loss-related rage can be intense and in bursts or osmotic and permeate the whole emotional landscape.
Rage gives place to sadness.
It is the sadness of the trapped animal, an existential angst mixed with acute depression. It is a paralyzing sensation, which slows one down and enshrouds everything in the gray veil of randomness. It all looks meaningless and empty. This, in turn, gives place to gradual acceptance and renewed activity. The narcissist is gone both physically and mentally.