Jonathan Frazens' The Corrections.
I've read this book about two months ago, and have the memory of a goldfish, so bear with me.
It's an excellent book, and I always admire authors that can write extraordinary things about ordinary life. These are the stories, in turn, of a family (The parents, older couple, the husband suffering from Parkinson, and their three (grown-up) children - the successful, unmarried daughter, the liberal university teacher and the married business man.
And god, do you start to hate all of the characters. I don't think I've ever read a book where I felt no sympathy at all for any of the people in it. They irritate you with their flaws, their actions, their obsessions. You want to throw the book out of the window and yet you keep on reading it. It's insufferable and fascinating at the same time.
So, all in all, 4/5, because it is ridiculously well written. It just put me in a very bad mood while I was reading it.