Worst book to movie

I always get excited when I learn a book I'm reading has been turned into a movie (BTW, cannot WAIT for the new Harry Potter movie this summer), but I've found a lot of people don't like going to these movies with me.
 
I'm quite critical of the storylines and the character development. Maybe it's snobby, but I just think these movie makers should take more caution to protect the integrity of the storylines I love so much.
 
Case in point Divine Secrets of the Ya-Ya Sisterhood. Amazing book. I couldn't put it down. If you've never read it, it's about a girl trying to learn the truth about her mother, why she abandonned her and her siblings for a while and why she couldn't connect with her children. The mother has three best friends who have been likes sisters to her for her entire life. The friends essentially kidnap the daughter before she makes a terrible mistake with her own fiance and forces her to learn what really happened to her mother.
 
If you're just sticking to the basic storyline, the movie does an OK job. But there are so many subplots to the story of Sidalee (the daughter) and Vi-Vi (the mother) that I think are crucial to the outcome of the story.
 
The movie depicts Vi-Vi as this monster of a woman who is forced into a loveless marriage and resents her family for the life she never wanted.
 
The book, on the other hand, depicts this woman who was once full of life, the belle of the ball, who got handed a lot of terrible hardships. Shipped away at a young age by her own mother. Losing her first love to war. It builds the story of a woman with a serious mental illness. It takes readers through the journey that led Vi-Vi to her breaking point. And the reader manages feel sympathy for Vi-Vi.
 
The movie takes most of that away. There are a few moments. When Vi-Vi's mom makes her return a ring her father gave her, you get the sense that Vi-Vi's mom resented her daughter, but if that's all you have to go on, the character of Vi-Vi seems complete heartless.
 
I was grossly disappointed in this movie. I don't think it would have taken much to bring out more of Vi-Vi's past (other than her wild side).
 
Tell me what, do you think is the worst book to movie?