My mother died about 5 years ago. She had a month or two left unbeknownst to me. One day I let it all hang out. Harangued her for about 40 minutes non-stop. Gave it to her, both barrels.
This was a woman who never did in all her life, ever mellow the hell out. She was ugly to the end.
Did me a lot of good to tell her off, and I recommend it, and I don't care how long they have left.
The only unfortunate thing about her dying is that she's not here so I can tell her off again. No way did I hardly scratch the surface.