Elizabeth Kübler-Ross's stage theory of dying was developed as a research project. The goal of the research project was to investigate how the terminally ill cope with dying.
Denial, anger, bargaining, depression, acceptance is the sequence of Kübler-Ross's "five stages of dying". Michelle who has started to yell at family members and her medical team whenever someone speaks to her and is irritable and verbally abusive is most likely in the anger stage.