Most of the couples on this list fell head-over-heels for each other, even if only for a short time — but in the case of "The Partridge Family" stars Susan Dey and David Cassidy, it seems to be a case of unrequited love. Dey played Laurie Partridge, the sister to Cassidy's Keith in the popular 1970s sitcom. Despite their familial status on-screen, Dey quickly fell for her co-star. Cassidy knew about her feelings, and when the show ended in 1974, they briefly pursued a relationship that culminated in a one-night stand. However, Cassidy's feelings for his co-star weren't equal to hers, and ultimately, he rejected her.
Two decades later Cassidy revealed the details of their relationship, explaining in his 1994 tell-all: "I find a certain sluttiness very attractive in a woman, and Susan just didn't have it." David later admitted to Desert News (via Inquisitr) that he lost touch with Dey in the early 1990s, probably because he aired details of their failed romance in his book.
Dey found love with Leonard Hirshan, with whom she welcomed a daughter. They later divorced, and she married TV producer Bernard Sofronski in 1988. Meanwhile, before his death in 2017, Cassidy racked up a series of marriages and divorces and had two children: a son, Beau, with his third wife, Sue Shifrin; and a daughter, "Arrow" star Katie Cassidy, from whom he was estranged, from an affair with model Sherry Williams.
