The beautiful Charlize Theron, 38, covers the June issue of Vogue
, in which the usually tight-lipped actress dishes about dating fellow Oscar-winner Sean Penn, 53.
"I really didn't see it coming," she says about their blossoming 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."
But she now calls the relationship, which the two have been refreshingly open about, "effortless." Penn even made a rare public appearance accompanying Theron to her premiere of A Million Ways to Die in the West on May 11, 2014.
"It just kind of naturally happened, and before I knew it, I was in something that was making my life better -- the people who really love me can see the effect it has had on me," she gushes.
Just don't expect her to walk down the aisle anytime soon.
"Let's put it this way: I never had the dream of the white dress," she explains. "And watching other people getting married? I think it's beautiful for them, but to be quite honest, usually I'm sitting there just devastated. It's supposed to be this night of celebrating love, and all you see is a couple separated all night making sure everybody else is OK. It just looks like a lot of work. And as you get older, you start sifting through the stuff that really matters."