"I did not f--k him," she says now, adding that the fling "wasn't innocent."
Kristen Stewart just opened up like never before about her 2012 romantic tryst with director Rupert Sanders, which reportedly led to her split from Robert Pattinson and Sanders' divorce from then-wife Liberty Ross.
When Stern asked his guest why she didn't scream that from the mountaintops after being photographed making out with her "Snow White and the Huntsman" director while she was dating her "Twilight" co-star and Sanders was married to Ross -- who was also in "Snow White" -- Stewart said, "Well, who's going to believe me? It doesn't even matter."
"It looked like... You know, you make out with a dude in public, it definitely looks like you did [have sex]," she said, admitting, though, that the fling "wasn't innocent."
Stewart's main gripe is that she was denied a role in the 2016 sequel, "The Huntsman: Winter's War," and she chalks it up to the scandal.
"We lived in a different time then, you know what I mean? I feel like the slut-shaming that went down was so absurd," she explained. "And they should've put me in that movie! It would've been better. Not to be a dick, but... They didn't put me in that movie because I went through such a highly publicized scandal, and so they were like scared of touching that."
Stern noted that was a "dumb move" by the studio, and Stewart agreed.
"I wouldn't say that I fell in love with the director," she made sure to note. "It was kind of a weird thing, but I definitely think that that movie... Ugh, it wasn't that big of a deal, you know what I'm saying? The work is so much more important! It's like, what do you care if I... I just thought that that movie actually -- we could have made a great second one, and we could have done it in a functional and healthy way. We didn't ultimately do that, and that's okay 'cause I did other stuff and it's fine, but yeah, that was weird."
"That was a really hard period of my life," she explained. "I was really young. I didn't really know how to deal with that. I made some mistakes. And honestly, it's no one's business. And, people get over shit like that, you know what I mean? It's really not a big deal. Basically, what I'm saying is, the work to me genuinely was ignored in a really sort of frivolous, silly, petty way. For a group of adult people who were supposed to be running studios and making films? Honestly, the film industry in Hollywood is so fear-based."
"I think they're idiots, because if you take a little risk and make something good, people will watch it and like it and pay you," she added.
Stewart took so much heat over her "affair" with Sanders that even Donald Trump chimed in on the matter.
"Robert Pattinson should not take back Kristen Stewart," he tweeted at the time. "She cheated on him like a dog & will do it again--just watch. He can do much better!" And, yes, that tweet is still up.
Robert Pattinson should not take back Kristen Stewart. She cheated on him like a dog & will do it again--just watch. He can do much better!— Donald J. Trump (@realDonaldTrump) October 17, 2012
Of the tweet, Stewart told Stern, "You would think he that had more important things to do. It's absurd and very embarrassing for him."
Despite Trump's public suggestion to Pattinson, he and Stewart got back together. "We went through a thing and it f--king sucked, but we really wanted to be together," she said.
Discussing her relationship with Pattinson during the height of "Twilight" pandemonium, Stewart explained, "It was [insane]. We wanted to keep it ours, so it was this thing of going like, do you live openly and share your life in a way that actually entitled you to living it sort of more freely and naturally, or do you put it on lock because you hate the idea of perpetuating this co-modified version of something that feels real to you? And you're like, 'No, I'm not selling you shit!'"
"But then you actually deprive yourself of so many experiences," she noted. "We didn't walk down the street holding hands because we were like, 'We don't wanna give it to 'em.' But then we didn't get to walk down the street holding hands, and it sucked."
During a later part of the interview, Stern said he believes falling in love on set is anyone's "biggest mistake," but Stewart maintained there was "nothing I could do." Agreeing with the media personality that there was immediate chemistry with Pattinson, Stewart explained she felt "so weird" "actually being honest about this."
"It's been so heavily consumed," she said of her past relationship with her former co-star. "I have this fear that people would assume that maybe it's kind of attention-y. Like, 'Ohhh, cool, you're still pushing that narrative?' But it's like, no, I've actually never been allowed to just say what happened because I was so self-conscious about seeming like an attention-seeker."
Despite the fallout, Stewart had nothing but good things to say about her ex.
"We were together for years. That was my first [love]," she said, noting she was "super in love with my high school boyfriend. Super, super f--king in love with him. But me and Rob were a little older, and it was just like, 'Guh-gung!' He's the best. He's the best."
When it comes to the countless rumors that their relationship was some sort of publicity stunt, Stewart still can't believe the speculation. "I had people genuinely asking me if that relationship was real or fake," she explained. "You really think at this point, after all these years, that that's how I live my life?"
Stern went on to ask his guest, "Was there a point you would've gotten married? Do you think?"
"I don't know," she replied, laughing. "I wanted to, yeah. I mean, I think... I've never been in..."
"If he proposed, you would've gotten married," Stern said to Stewart.
"I don't know," she responded. "I'm not a super duper traditionalist, but at the same time, every relationship I've ever been in, I thought that was it. Maybe one or two, but I've never really been the most casual [dater]."
When asked if she thinks she'll get married one day, Stewart -- who is currently dating screenwriter Dylan Meyer following her split from model Stella Maxwell -- said, "Yeah, for sure."
"I wanna be on a team," she added, "and I want the team to have a name."
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