Prince Charles and Camilla
Prince Charles and Camilla Parker Bowles first began dating in 1970, but the romance didn't last long and they both went on to marry other people. Charles wed Lady Diana Spencer in 1981 and they had sons William and Harry together. But the former couple apparently never stopped loving each other and began an affair in the 1980s. "There were three of us in this marriage, so it was a bit crowded," the late Princess Diana famously said during an interview when asked about her marriage problems. She and Charles divorced in 1996 and Diana was killed in a car crash the following year. Charles and Camilla finally walked down the aisle in 2005.