Grief and depression are different. It is possible to grieve without being depressed, but many of the feelings are similar.
However, about 33 per cent of bereaved people also have a depressive illness one month after the loss, and 15 per cent are still depressed a year later.
Symptoms that suggest a bereaved person is also depressed include:
- intense feelings of guilt not related to the bereavement
- thoughts of suicide or a preoccupation with dying
- feelings of worthlessness
- markedly slow speech and movements, lying in bed doing nothing all day
- prolonged or severe inability to function (not able to work, socialise or enjoy any leisure activity)
- prolonged hallucinations of the deceased, or hallucinations unrelated to the bereavement.
It is difficult to judge who will or won’t suffer depression after a bereavement. However, risk factors thought to increase the chance include the following:
- a previous history of depression
- intense grief or depressive symptoms early in the grief reaction
- few social supports
- little experience of death.
https://www.netdoctor.co.uk/healthy-living/a640/grief-bereavement-and-depression/