Katherine Heigl quickly developed a reputation as an industry diva after she rescinded her Emmy nomination for her work as Dr. Izzie Stevens on “Grey’s Anatomy” nearly eight years ago. Heigl opened up about her apology to the series’ creator, Shonda Rhimes, and talked about some of her other missteps in Hollywood.

"I didn't feel good about my performance, and there was a part of me that thought, because I had won the year before, that I needed juicy, dramatic, emotional material," Heigl told Howard Stern on his SiriusXM radio show Wednesday. Taking herself out of the running caused tension with Rhimes and her fellow co-stars Ellen Pompeo, Patrick Dempsey, Sandra Oh and Justin Chambers.

Heigl, now 37, felt “embarrassed” when she reflected on her actions: "So I went in to Shonda and said, 'I'm so sorry. That wasn't cool, and I should not have said that.' And I shouldn't have said anything publicly. But at the time, I didn't think anyone would notice … I just quietly didn't submit, and then it became a story, and I felt I was obligated to make my statement.”

It wasn’t just “Grey’s Anatomy” where Heigl felt herself in the middle of turmoil. She also caused strife with “Knocked Up” co-star Seth Rogen when she said the movie was “a little sexist” in a 2007 Vanity Fair interview. It “paints the women as shrews, as humorless and uptight” and was hard for her to love, she added at the time. 

Izzie Stevens Former "Grey's Anatomy" star Katherine Heigl, pictured as her ABC character Dr. Izzie Stevens, apologized for embarrassing the show's creator, Shonda Rhimes. Photo: ABC

While Heigl would work with Rogen again, she didn't think the feeling was mutual. “I think he’s really mad at me,” the actress told Stern, recalling when Rogen ignored her at a restaurant after the Vanity Fair article debuted. “I didn’t quite realize it was as serious as it was,” she said. “I was like, ‘Oh, you’re really mad.’ I didn’t realize it was that bad.” Now, however, Heigl understands why. “I get it," she reflected. "It was an immature, dumba-- moment.”

The former "Grey's Anatomy" star has since matured. Heigl credited her therapist with getting her head in the right place. "He was recommended by a friend, and I didn't know who else to go to … it was convenient, and he ended up being absolutely wonderful and just my speed," she said. "I've only gone about five times in my life … For me, it's a lot about wanting to be able to sleep at night."

The actress left “Grey’s Anatomy” in 2010 after rumors swirled she was “difficult” to work with. Her career took a nose dive. Her starring movie roles vanished, and by 2016, the only gigs she could seemingly book were commercials for kitty litter and Nyquil.

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