I think it must have been out of spite for her son that Lizzie did not abdicate. What do you think? I mean she croaked when the guy is 73!!! If that's not spite, I don't know what is.

Her mother abdicated to Liz, so why not her to allow her son to enjoy being king while he wasn't completely "sausage fingers" decrepit??

I figure the guy must have had a lot of resentment she made him wait till he's at death's door himself to be king. I predict he won't live past 2023, at which point there probably be a huge revolt against the monarchy and the peoples will try to end it once and for all, rebelling against such a young king (William).