What Alice Forgot by Liane Moriarty (2009)

Absolutely adored this novel about a woman who falls down at the gym, hits her head and wakes up with amnesia. Her last memory is of being pregnant with her first child, happily married, and a new homeowner. But it's actually ten years later, she has three children, and is in the midst of a messy divorce. Not only that, but her sister is oddly distant. The beauty of this book is in Alice's slow discoveries of what has happened in the past year, how she (and others) have changed and why. Wonderful, vivid characters, and Moriarty is wonderful with relationships, particularly sisterly relationships. Delightful and humorous but full of insight and complexity as well.