Columbia University psychiatry professor M. Katherine Shear, MD speaks of grief as “a shorthand word for a complex, time-varying experience that is unique for each person and each loss.” As it is a normal response to loss, it does not count as a disorder.
However, according to the American Psychological Association, “broad changes to all personal relationships, a sense of meaninglessness, a prolonged yearning or searching for the deceased, and a sense of rupture in personal beliefs” can mark the beginning of complicated grief, which resembles but is not exactly the same as depression.
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