Grief (novel)
During the course of the novel, the ideas of the stages of grief are introduced. The stages are denial, anger, depression, and acceptance. The narrator, as well as other characters in the story, slowly passes through these stages in trying to deal with death.
George Bonanno
That people are resilient even when facing extreme stressors or losses contradicts the stages model of grief. Many resilient people show no grief. They therefore have no stages of grief to pass through. Until Bonanno, therapists and psychiatrists considered the absence of grief a pathology to be feared, rather than a healthy outcome.