The old adage "Don't mix business and pleasure" doesn't apply to the music industry. This Valentine's Day, we're showcasing some artists that found love in the workplace. Whenever members of a group get together, it can result in an invigorating period of creativity. . . or things crash and burn when the romance ends. What follows are 15 examples of noteworthy intraband relationships and how they – and their bands – fared, for better or worse. By Daniel Kreps