Funeral of a friend's father

Visiting the funeral service of a friend's father yesterday shook me more than I had expected. He had had Alzheimer's for 8 years, and his death is not only cause of grief, but certainly also a kind of relief for the family. Still it made me sad to think about him, a former mathematics professor and someone whom I admired for his intellectual capacity, being deprived of exactly this and suffering without being able to understand for years.