Heart of the Matter by Emily Giffin

This is the first book I've read by this very popular author. I can see why she is so popular - very easy to read, fast, and fun, and with some good food for thought about a difficult issue - infidelity.  The novel deals with this topic in a pretty realistic way. The story is told from the point of view of the two women: Tessa, the wronged wife, and Valerie, the woman her husband Nick gets involved with. It's not a steamy sexy novel, either. Nick doesn't cheat with a beautiful sexy bombshell who seduces him, but rather, with the single mother of a child he treats in his job as a reknowned pediatric surgeon.
The characters are all sympathetic (the two female characters more so than Nick); the reader doesn't hate Nick, Valerie, or Tessa. The author manages this by telling the story from both points of view.
The weakest characters are secondary characters: Tessa's brother and his wife, and Tessa's friends are pretty vapid and petty. But the author makes it clear that Tessa is not really like them or particularly comfortable in her new role as a stay at home suburban tennis playing mom. She takes on this life to be with her children.
I think I'll read more of her novels when I am in the mood for a quick and easy read, but with a good storyline and rich characters.....I hope the other novels are as good!