As part of their reaction to loss, some grieving individuals show symptoms characteristic of depression, such as feelings of sadness, insomnia, poor appetite and weight-loss. While these these symptoms are a 'normal' reaction to a major loss, if they persist for more than a few months, you should seek professional help. Expressing feelings of guilt, worthlessness or anger, leading to thoughts of suicide, should be taken seriously.

Grieving increases our vulnerability to illness and it is not unusual to experience a series of minor illnesses during the first year following a loss. research has also shown that a major loss can be a precursor to serious illnesses such as cancer and heart disease. 

Grief commonly follows 6 stages: Denial, anger, bargaining, depression, acceptance (followed by) hope for the future.