Stewart and Pattinson's highly publicized relationship ended following the release of the last "Twilight" film, after the actress kissed her "Snow White and the Huntsman" director, Rupert Sanders.
On Friday, Stewart was asked during a talkback event with Variety at the Sundance Film Festival what she thought about Trump's tweets, now that he's the president.
"He was mad at me a couple years ago, really obsessed with me a couple years ago, which is fucking crazy," said Stewart, who was in town to promote her short film, "Come Swim." "I can't even understand it. I literally cannot even understand it. It's such far-out concept that I don't want to believe that actually is happening. It's insane."
At the time, Stewart said she dismissed Trump's tweets because he was a "reality star." But now she sees his social media obsession with her as much more troubling.
"At that point, he was just, like, a reality star. I had no reference. It wasn't like really a thing," Stewart added. "But in retrospect, somebody reminded me of that and I was like, 'Oh my gosh, you're right!' He's probably, like, going to tweet about this."
Probably, Kristen. Probably.