I think that if you are lucky when a loved one is lost to you there will be no regrets regarding how well you knew them. You will have had the time and oppertunity to ask all of the questions that you wanted to and you would have been told all the stories they knew. When that loved one is a parent it seems to me most often that what you didn't know is exactly what would have brought you the most peace and understanding when they passed.
In Amy Tan's The Bonesetter's Daughter, middle aged ghostwriter Ruth Young is losing a parent by inches. Ruth is a woman who has defined herself in many ways but now suddenly she sees herself only as the daughter of a newly diagnosed Alzheimer patient, her mother LuLing. LuLing was raised outside of Peking by her beloved Precious Auntie. When her Aunt is lost to her through betrayal and deceit, LuLing eventually makes her way to America. As LuLing wanders in and out of the tenacious disease that will soon control her she struggles to tell Ruth all she needs Ruth to know to stay strong and find her own happiness. Ruth doesn't understand what she presumes are her Mother's ramblings. Partly to pass the time and partly to escape her Mother's chatter Ruth begins a translation of her Mother's diary. It is then that she learns of the traumatic events of her Mother's life and begins to understand her Mother's courage and desire to communicate with her.
My bare bones description of the story should not be taken as that's all there is. AmyTan has layers upon layers (Ah! The old multilayered!) of back story and family history throughout Bonesetter's. How she can manipulate all that fascinating information into the personalities of her characters is spectacular. Reading the absorbing life stories of generations only to have them come skillfully dancing back to the present and all of it's worries and to matter? That is masterful writing. That is storytelling.
I could say that mother daughter relationships are not new ground for Amy Tan but that's like saying that men fading out of their prime is not new territory for Philip Roth. This is what these authors write about. You read them because you have an interest in that and because they write so well. End of story--which is a shame!
P.S. In case you were wondering you can get any or all (I would recommend the all) of Amy Tan's great novels---and I can say that now that I have read them all---at any Independent Bookstore. Good news, right?