The Time Traveler's Wife by Audrey Niffenegger. The story of Henry, a time-traveler who has no control over when and where he disappears through time, and Clare, his wife. The time travel aspect adds an interesting twist to a really sweet love story. This is one of my all-time favorites.
“And when her lips met mine, I knew that I could live to be a hundred and visit every country in the world, but nothing would ever compare to that single moment when I first kissed the girl of my dreams and knew that my love would last forever.” ― Nicholas Sparks, Dear John