Grief is generally associated with the loss of a person/relationship/community/homeland that we have loved.
It can also result from the loss of a happy future, which we had planned but will now never happen.
However, this CNN article tackles the uncomfortable topic of the death of an unloved one. This is sometimes known as “complicated/unresolved” grief. The reality is that this is a very common situation, and it is a difficult one to navigate.
https://www.cnn.com/2013/09/24/living/death-anger-reddick-obit/index.html