Ryan Phillippe and Reese Witherspoon (1999-2006)
Ryan Phillippe and Reese Witherspoon’s chemistry in 1999’s Cruel Intentions didn’t require much acting — the absurdly hot co-stars were already dating when filming began. In fact, their flirtation actually sparked two years earlier, the night of Reese’s 21st birthday. After their marriage on June 5, 1999, they produced two of Hollywood’s most adorable kids: Ava and Deacon. Unfortunately, marital bliss didn’t last: they separated in October of 2006 and filed for divorce a month later. Ryan and Reese cited “irreconcilable differences,” but Australian actress Abbie Cornish was rumored to have come between them.