I confess to having memory problems like that. I've heard that folks with Alz can be combative. Perhaps that's from the confusion and fear they're experiencing.

I've also come home from work hungry and in a bad mood, which eventually leads to me yelling.

He's definitely going through something, but you certainly don't deserve to be yelled at!

Now that I'm aware of my behavior and triggers, I've adopted a routine that before I enter the house after work, I release the frustration from the work day, washing it away, almost like taking a quick shower. It took me many years to get to this point, with therapy to prod me along.

Perhaps therapy was suggested in this thread, so I won't repeat it.