A Week at the Lake by Wendy Wax. The book is being released by Berkley on June 23, 2015.
Amazon says this about the book: Twenty years ago, Emma Michaels, Mackenzie Hayes, and Serena Stockton bonded over their New York City dreams. Then, each summer, they solidified their friendship by spending one week at the lake together, solving their problems over bottles of wine and gallons of ice cream. They kept the tradition for years, until jealousy, lies, and life’s disappointments made them drift apart.
It’s been five years since Emma has seen her friends, an absence designed to keep them from discovering a long-ago betrayal. Now she’s in desperate need of their support. The time has come to reveal her secrets—and hopefully rekindle their connection.
But when a terrible accident keeps Emma from saying her piece, Serena and Mackenzie begin to learn about the past on their own. Now, to heal their friendship and their broken lives, the three women will have to return to the lake that once united them, and discover which relationships are worth holding on to . . .