Lots of love to you, Willow. I lost a family member to addiction when he was 25. I know the complete bafflement (if that's a word) around how to handle things. I was very young at the time, but I do remember that DENIAL was huge in that circumstance. To the point where there was never an obituary published, and his funeral was family only. Most people who went to high school with him have no idea he's dead.
I think, based on my experiences, that you can honor her memory while acknowledging the horrid disease that ended her life. I think learning about alcoholism, and teaching her children about it, would be a wonderful gift to them in her honor.