I just finished Carole Radziwill's book, What Remains: A Memoir of Fate, Friendship and Love (buy direct) and have to say I really loved it. Her book is about her husband, a cousin of JFK, Jr., and the cancer that he struggled with, but it's also about her friendship with Kennedy's wife Carolyn.
One thing that really blew me away was how easy their friendship seemed to be from the beginning. These were mature, smart women, and there wasn't the catty behavior that people seem to assume exists with every female friendship. It doesn't. (Note: if your friend is catty and competitive, maybe it's time to find someone who will act like a real friend.)
The other thing that made an impact was how ready Carolyn Kennedy was to be a friend and sit with Radziwill all the times her husband needed surgery and treatment. It can be a very lonely life when you're sick, and friends have a tendency to scatter in those type of difficult times. But the two women seemed to get even closer because of it.
JFK, Jr., his wife, and his sister-in-law died in that terrible plane crash just three weeks before Radziwill's husband. As I read that, I tried to imagine how devastating it must have been to lose the friendship and support network you had come to rely so heavily on, just as your husband is about to die and you need them the most.
It's an incredible story, and beautifully written.