View gallery Image Credit: Getty Images Donald Trump Jr. and Kimberly Guilfoyle became a famous political power couple before his father, Donald Trump Sr., became president. However, after almost six years of dating, reports surfaced about a new woman in Don Jr.'s life: his fiancée, Bettina Anderson. So, why did he and Kimberly break up? She finally broke her silence on his new relationship. Below, get all the details we know about Don Jr. and Kimberly's breakup. When Did Donald Trump Jr.