Answer:
Chronic Grief.
Explanation:
George A. Bonanno is a professor of clinical psychology at Teachers College, Columbia University, U.S.A. and was born in 1950. According to my research on Bonanno's studies, I can say that based on the information provided within the question the type of grief that is being defined in the question is called Chronic Grief. Like mentioned in the question this is a hightened grief that affects the widow/widower continuously and for a long period of time after a spouses death.
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