I have not lost a family member due to a deliberate act, so my point of view is conjecture- but I cannot imagine living with the anger that would result if I refused to forgive someone in that case.
My point is that repentance and forgiveness are so intertwined that they almost can’t be separated.
Many people like the idea of forgiveness especially with God but NEVER approach the repentance part. Has God forgiven your sins if there is no repentance? Is the transaction complete?
If the transaction is not completed, is it really forgiveness? I propose it is something else, giving the situation over to God, giving the anger over to God. That is why our “forgiveness” with others is so hard to deal with and comes back again and again, because it is not complete.
But, giving it over to God can be a completed transaction.
But of course now one has to take some time and reflect on what repentance is...............................