Shelley Duvall, who famously co-starred in “The Shining,” is dead after a painful battle with diabetes.

Dan Gilroy, Shelley’s life partner for decades, tells TMZ … he found Shelley unresponsive in their home in Texas at 7 AM Thursday. He says Shelley had been under hospice care, and bedridden, for the last few months while dealing with complications from diabetes. He says she died in her sleep.

Shelley had the unforgettable role of Wendy Torrance in Stanley Kubrick‘s “The Shining” — she was on the other side of the door when Jack Nicholson smashes through the door with an ax, yelling … “Here’s Johnny!”

Years earlier, she’d been discovered in Texas by director Robert Altman … and went on to star in 7 of his movies, including … “3 Women” and “Thieves Like Us.”

She also famously played Olive Oyl, opposite Robin Williams in “Popeye.”

In 2016, Shelley appeared on “Dr. Phil” to say she was battling mental illness, and needed help.

Shelley was 75.