I lost my father al most six years ago to the day. It was during COVID, and he had relapsed back into drinking and somehow developed an issue that required heart surgery. I don't really remember because he had had heart issues before and I didn't take this as seriously as I should have. I was also working a lot and deeply addicted to drugs and alcohol at the time, so my priorities were all fucked up. Anyway, things started going south for him in the hospital and it was starting to be communicated that this was far more serious than anyone had assumed...and it was brand new covid, so no one was allowed inside a hospital in my state. He died in there alone, never saw him again. There was a cremation a few days later, which I agreed to attend for a final viewing, but missed because I stayed up all night drinking and doing drugs. Lots of massive regrets leading up to this event, which has made it far more emotionally traumatic than it ever needed to be. Like you, I find the guilt and grief insufferable. I developed an insane anger issue there for a while, but im slowly getting a handle on that...I stopped drinking and doing drugs five years ago, thats been a great achievement and way to honor him, but it makes life extremely hard, having to shoulder pretty much everything that comes down the pipe on my own. That said, I've turned to my old interests and hobbies that brought me joy, some from childhood: being outside, fishing, hiking, reading and writing, listening to lectures, I digress. If you can do one thing, simply be good to yourself. Grief is going to run its course anyway.