Anticipatory grief
The five stages namely, denial, anger, bargaining, depression, and acceptance proposed by Elisabeth Kübler-Ross in her model of grief describe the process by which people undergo after a loss. Anxiety, dread, guilt, helplessness, hopelessness, and feelings of being overwhelmed are also common. However, it is important to note that anticipatory grief is not simply normal grief begun earlier.
Grief
Other researchers such as Randolph Nesse have proposed that grief is a kind of psychological pain that orients the sufferer to a new existence without the deceased and creates a painful but instructive memory. If, for example, leaving an offspring alone at a watering hole led to the offspring’s death, grief creates an intensively painful memory of the event, dissuading a parent from ever again leaving an offspring alone at a watering hole. More recently, Winegard, Reynolds, Winegard, Baumeister, and Maner argued that grief might be a socially selected signal of an individual’s propensity for forming strong, committed relationships. From this social signaling perspective, grief targets old and new social partners, informing them that the griever is capable of forming strong social commitments. That is, because grief signals a person's capacity to form strong and faithful social bonds, those who displayed prolonged grief responses were preferentially chosen by alliance partners. The authors argue that throughout human evolution, grief was therefore shaped and elaborated by the social decisions of selective alliance partners.