Charlize Theron is definitely smitten with her boyfriend (and rumored fiancé), actor Sean Penn.

In a new interview with Esquire, the 39-year-old "Mad Max: Fury Road" star gushes about the Oscar-winning actor, who she was friends with for 20 years before things took a romantic turn in early 2014.

"I think that for both of us there was never a moment where we thought that this -- what we have today -- would ever even be a possibility. Evereverever," she tells the magazine. "I think we’re both finding ourselves at this moment in our lives kind of shocked. Both of us. Just when you think you know how things are supposed to go down, life just kicks you in the ass and guess what? You don't have a clue."

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Obviously, Charlize is attracted to her 54-year-old beau.

"I’m a very, very, very lucky girl," she gushes. "Very lucky. He's hot. He is hot. How do you say that in an interview? You're a 40-year-old woman sounding like a 16-year-old. There's something beautiful about that, but you lack the articulation of really saying what it's like when somebody walks into your life and makes you see something that you really never thought you'd be able to see. If somebody had said to me, 'This is what it will be,' I would've said, 'F--k off.' As you can see, it makes me smile."

Currently, rather than thinking about marriage, she's enjoying the moment.

"We get so stuck in wanting to predict the future that we forget the moment that we're in," Theron explains. "And the moment that we're in is just really good. It’s really good, really nice. 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."

Charlize is busy promoting the highly anticipated "Mad Max" sequel, and confirms the rumors that she and co-star Tom Hardy didn't exactly get along on set.

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"We f--kin' went at it, yeah," she admits. "It was the isolation, and the fact that we were stuck in a rig for the entire shoot. We shot a war movie on a moving truck -- there's very little green screen. It was like a family road trip that just never went anywhere. We never got anywhere. We just drove. We drove into nothingness, and that was maddening sometimes."

Still, she has deep admiration for the 37-year-old actor.

"I'd rather have that honesty working with someone than someone who fake-smiles through something -- especially for actors, when your job is to go for the emotional truth," she explains. "When you're with somebody and you don’t feel like you’re in their emotional truth, then you don't trust them. I think good actors go all the way."

She also stresses that there's no hard feelings between the two. At the end of the shoot, Tom actually gave Charlize a hand-painted self-portrait with the following inscription: "You are an absolute nightmare, BUT you are also f--king awesome. I’ll kind of miss you. Love, Tommy."

"We drove each other crazy, but I think we have respect for each other, and that's the difference," she now says about their relationship. "This is the kind of stuff that nobody wants to understand -- there's a real beauty to that kind of relationship.”