Introduction to Ali Reynolds - getting her established in Sedona, AZ after being fired from her job as a news broadcaster, and learning that her husband has not one - but two girlfriends - although only one of them is pregnant. 
With the help and encouragement of her 21 yr old son from her first marriage, Ali starts a blog to share her story of being "Cut Loose" . She includes a comments section that leads to some interactions with people across the country - including a woman who's abusive husband blames Ali for his wife leaving him. 
Oh - but - what about the Edge of Evil - and the opening chapter that includes a car being pushed over a cliff with an already dead body falling out as the car tumbles down the hillside? That car contained Ali's best friend - recently diagnosed with ALS. Her death is declared a suicide  - a diagnosis that Ali and Ali's assistant at the YWCA do not agree with - especially when the suicide note was typed on a computer and not handwritten on a greeting card. 
Ali interacts with her bestie's children, cheating husband and parents. She also fills in as a waitress at her parents' restaurant when her father is injured in a snow boarding accident. She gets access to Reenie's email and learns about Reenie's concern about her children's trust accounts. 
Suddenly - when the book has been moving along, throwing a few red herrings about Reenie's death, establishing issues with Ali's upcoming divorce, her parents deciding not to sell their restaurant, Ali establishing a friendship with the police detective - Ali is  run off the road by a woman driving a BMW - a woman who

turns out to be Reenie's sister. She syphoned money out of the trust funds established for Ali's children - and had been embezelling money from her father's company. She and her husband killed Reenie -

all neatly wrapped up in a matter of minutes/pages at the end. A little too abruptly for me.