I grew up with it also my grandpa who was a great man sort of famous in my city because of his construction company. Punched my grandma once while they were in bed at night because he thought he was back in war (He was in WW2) chased us out of the house with a fireplace poker, ran off multiple times at night, left my grandma at the grocery store just drove off left her there. It's one of the saddest diseases because your mind just doesn't work right anymore. I feel for Marty.