What is 'normal grief'? Caroline Lloyd has written a remarkable research-based book on grief for people who support the bereaved and also for the bereaved themselves. She explains the fascinating history of grief theory, the effects internet can have on bereaved and the terrible toll when a loss isn't acknowledged by society.
https://thegriefgeek.com/
https://www.easons.com/grief-demystified-caroline-lloyd-9781785923135
https://www.amazon.com/Grief-Demystified-Introduction-Caroline-Lloyd/dp/1785923137