Am I missing a trick here?

Context:
I had an abusive father for my whole life, I say had as he passed away in 2019, well as he was so abusive I hated him and I was glad that he died, well I’ve been told that I should forgive him not for him but for me, (I don’t understand this personally, but oh well) well tonight I took it upon myself to write him a letter (I know I can’t send it to him as he’s no longer of this planet) well I thought that if I said how I felt and said that I forgave him I’d feel better but I don’t I still feel meh, am I missing something? Or am I just so badly broken that this is it?
Am I missing a trick here?
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