Symbolism of Alzheimer's Disease

Alzheimer's Disease might be described as a disease of the memory: it eats away at a person's recollections, leaving him / her with virtually no memory of themselves or of the people around them. The presence of Alzheimer's in the novel (specifically in the character of Ina Ott and the reactions of those around her) can be seen as a facet of the novel's thematic interest in the relationship between past and present: specifically, how the forgetting of the past can lead to either unhappiness and suffering (in Ina's case) or healing (in the case of Silas and Larry).