I think it might be a variation of a “complicated grief”.
You are grieving yet you have many bad memories and maybe had a sense of relief when he died, and now guilt of feeling relief brings even more intense grief. And it mixes with good memories and it’s kind of normal in that situation. That’s my take on it.
My stepkids lost their abusive mother last year, one had no relationship with her (for a good reason)and the other only occasional communication, they were very torn between grieving and relief that life long source of stress dealing with her is gone. They both shared that they didn’t know how to feel. Their life is so much better now yet she was their mother and they did have some good memories. So they had very conflicting feelings at first.
I apologize if I am not helpful