James Patterson: Sam's Letters to Jennifer [2004]

When Jennifer returns to the resort village where she grew up, she finds a series of letters in which her grandmother reveals a huge secret she has concealed for decades: that her great love is not the man she married. Jennifer herself thinks she could never love again, but before she knows it, is caught up in the greatest flight of exhilaration she's ever known. Then, just as suddenly, she learns that this new love comes with an unbearable cost...