The Husband's Secret: Liane Moriarty

At the heart of The Husband's Secret is a letter that's not meant to be read...
My darling Cecilia,
If you're reading this, then I've died...
Imagine your husband wrote you a letter, to be opened after his death. Imagine, too, that the letter contains his deepest, darkest secret--something with the potential to destroy not only the life you built together, but the lives of others as well. And then imagine that you stumble across that letter while your husband is still very much alive...
Cecilia Fitzpatrick has achieved it all--she's an incredibly successful businesswoman, a pillar of her small community, and a devoted wife and mother. But that letter is about to change everything--and not just for her. There are other women who barely know Cecilia--or each other--but they, too, are about to feel the earth-shattering repercussions of her husband's secret.