Remember the time when Sean Penn basically said he'd discount both his previous marriages (to Robin Wright and Madonna) because Charlize Theron is the only woman he's ever really wanted to marry? He may regret saying that now she's reportedly ended things with him after 18 months of dating. 

According to Vanity Fair, things in Cannes didn't go so well for the couple, where the 39-year-old actress was promoting Mad Max: Fury Road. A well-placed "mole" said: "Theron... was the one to break things off with the fellow Oscar winner..." 

Meanwhile, "multiple sources" also confirmed news of the split to Us Weekly.

Last year, when speaking with Vogue, Theron said of the relationship: “Sean and I have known each other for 18 years. We were just really good friends. And it's been slow going because you are aware that you could screw that up and lose it. We had to think about it... We get so stuck in wanting to predict the future that we forget the moment that we're in. And the moment that we're in is just really good... The marriage thing is always so strange to me anyway. I love the possibility of anything, but I'm really enjoying myself and the everyday moment and how that coincides with my son and my life and my friends."

As for the reported engagement, a source said: "There's no ring, but they are committed."