Sadness is considered a normal, healthy emotional reaction to minor losses and disappointments. Sadness is very transient, lasting only several minutes, a few hours, or, at most, a few days. It is unpleasant but typically doesn’t interfere with your functioning. Normal, minor bouts of sadness don’t knock you off your feet.
Grief is a much more intense and sometimes devastating human experience. However, it is considered an inevitable and normal emotional reaction that people in every culture across the world experience after a major loss, such as the death of a loved one or a divorce. Grief tends to have a major disruptive effect on the lives of the grief stricken and can result in prolonged periods of sadness, loneliness, and mourning, which can last anywhere from a few months to several years. Normal grieving may last a very long time; broken hearts do not mend quickly.