It’s a myth that she was singled out and abused on set. At most she’s said he’s a perfectionist and runs a difficult set, but she’s never claimed it was something criminal going on. I’ve seen documentary footage of the making of The Shining where Kubrick will be yelling something at her, then they’ll both be smiling and laughing a few moments later. It seems like it was a demanding acting job for her, but it wasn’t some inhumane treatment like what gets mythologized about

Here, an interview with her from 2021 where she only says nice things about Kubrick:

Asked whether she felt Kubrick had been unusually cruel or abusive to her in order to elicit her performance, as has been written, Duvall replies: “He’s got that streak in him. He definitely has that. But I think mostly because people have been that way to him at some time in the past. His first two films were Killer’s Kiss and The Killing.” I pressed her on what she meant by that: Was Kubrick more Jack Torrance than Dick Hallorann, the kindly chef played by Scatman Crothers? “No. He was very warm and friendly to me,” she says. “He spent a lot of time with Jack and me. He just wanted to sit down and talk for hours while the crew waited. And the crew would say, ‘Stanley, we have about 60 people waiting.’ But it was very important work.”

If you want to talk about someone abusing her, talk about that asshole Dr. Phil

The myth that Shelley Duvall was horribly abused by Stanley Kubrick on the set of The Shining and that’s why she left acting. It’s nothing but rumor and speculation by randos on the internet with very little basis, and it’s frankly disrespectful of Shelley Duvall’s work as an actor.