The Love of My Life by Rosie Walsh

Emma was quite certain she’d never fall in love again. But then she met an obituary writer, Leo, and within months, they were engaged. Seven years later came Ruby, their daughter, and then John Keats, their rescue dog. Now Emma, a marine biologist, has her perfect little ecosystem. They are happy, crammed into the tiny house her grandmother left her.
Leo was adopted as a baby, and this noisy, joyous little family is the first place he has ever felt he belongs. In fact, everything would be just perfect if Emma was who she said she was. If Emma was even her real name . . .
Because of Emma’s preeminence in her field, Leo is asked to write his own wife’s obituary while she is still alive. That’s when he finds that the woman he thinks he knows doesn’t really exist. As Leo starts to unravel the truth about the stranger in his bed, Emma’s old life breaks out of the carefully cultivated shell she created, threatening to wash away everything she has worked so hard to build.
When the very darkest moments of Emma’s past finally emerge, she must somehow prove to Leo that she really is the woman he always thought she was.
But first, she must tell him about the love of her other life.