Comment by Jolter

Not all Alzheimers patients get aggressive/angry. I know it happens, I’ve known one person who did almost exactly what you describe above. He lived with his partner of many years, and seemed superficially very cogent and together. It was just that he started to see insults and conspiracies against his person everywhere around him. Not until later did the cognitive and memory decline become apparent, giving him a diagnosis that explained his bad behavior.

But my personal anecdata puts that man in a minority. None of my older relatives with Alzheimer’s have become aggressive or troublesome. Worry, anxiety and confusion seem to be much more common states of mind, which admittedly also doesn’t seem like such a fun way to spend your days.