Elizabeth is Missing by Emma Healey

Living alone, Maud is descending into dementia. Despite having her daughter, Helen, nearby, and a caregiver that looks in on her every day, Maud is a danger to herself and others. She spends her time thinking about her older sister, Sukey, who disappeared over fifty years ago, and her current good friend, Elizabeth, whom she believes something bad has happened to. In her first novel, Healey writes a novel that is more about living with dementia than psychological suspense (which is what I was expecting). A read-alike for Alice LaPlante's Turn of Mind.