In an interview with the New York Post, the "Grey's" veteran opened up about the changes that have affected the show in its nearly 10 seasons.
"Hurt feelings, combined with instant success and huge paychecks started things spinning out of control," she said. "The crazier things got, as I watched all the tumult with Isaiah and then the Katie thing, I started to focus on the work."
Pompeo, 43, says she escaped the drama by trying "to not pay attention to all the noise around me." She credits her "Boston, blue-collar upbringing" for that mentality.
However, she recalls Heigl's departure as being particularly "tough."
"You could understand why she wanted to go -- when you're offered $12 million a movie and you're only 26," she said. "But Katie's problem is that she should not have renewed her contract. She re-upped, took a big raise and then tried to get off the show. And then her movie career did not take off."
Heigl has reportedly asked show runner Shonda Rhimes for the opportunity to come back to "Grey's" and reprise her old role. However, Izzie Stevens has never returned.
Pompeo also recalled Isaiah Washington's departure, and how she might have had something to do with it.
“Shonda really wanted to put a black man in the mix. I didn’t think they were really going to put an interracial couple on the show and I didn’t want him. It was too close to home,” she said in referrence to her real-life African-American husband Chris Ivery. "I said I wanted that Dempsey kid. I think that once Isaiah did not get the role it backfired."
In the end Pompeo is happy to have stayed in the show.
“Actors always think the grass is greener somewhere else. I didn’t want to do that,” she says. “I have an amazing life. I have a house five minutes from the studio, I have a house in the Hamptons, a house in Malibu, a beautiful daughter whom I see every night, and it’s all because I didn’t leave ‘Grey’s Anatomy.’”