IFS with Grief
Grief is a whole cast of parts — some contradictory

Grief typically involves many parts: the one who misses, the one who's angry at being left, the one who feels guilty, the one who wants to move on, the one who won't let go. Meet each.
Common grief parts: missing, angry, guilty, relieved, holding-on, moving-on, protector-of-memory, betrayal.
Grief is not one thing
It's a whole cast of parts, some contradictory. All of them need a turn. The goal isn't to resolve the grief — it's for Self to hold all of it, together, with love.