LOS ANGELES, CALIFORNIA: Katherine Heigl has reflected on her departure from 'Grey's Anatomy' in 2010 following rumors of on-set feuds. Besides, she was known for having a reputation for being difficult at work.

In more than 100 episodes of the ABC medical drama, the 'Firefly' actress played Izzie Stevens, however, she quit the show midway through season six's production in 2010.

'I was so naive'

"I was so naive. I got on my soapbox and I had some things to say, and I felt really passionate about this stuff," Katherine said on Variety. "I felt really strongly. I felt so strongly that I also got a megaphone out on my soapbox. There was no part of me that imagined a bad reaction."

She continued, "I felt really justified in how I felt about it and where I was coming from. I’ve spent most of my life — I think most women do — being in that people-pleasing mode. It’s really disconcerting when you feel like you have really displeased everybody. It was not my intention to do so, but I had some things to say, and I didn’t think I was going to get such a strong reaction."

'Because I was confused!'

Heigl further said, "I was in my late 20s. It took me until probably my mid-to late-30s to really get back to tuning out all of the noise and going, “But who are you? Are you this bad person? Are you ungrateful? Are you unprofessional? Are you difficult?” Because I was confused! I thought maybe I was. I literally believed that version, and felt such shame for such a long time, and then had to go, “Wait. Who am I listening to? I’m not even listening to myself. I know who I am."

'I think that gave me this confidence that was a false sense of confidence'

Katherine also discussed how her "confidence" from appearing on the popular show caused her to become "mouthy." "Then 'Grey's Anatomy' hit and the success happened. I think that gave me this confidence that was a false sense of confidence. It was rooted in something that couldn’t and maybe wouldn’t always last for me. So then I started getting real mouthy, because I did have a lot to say, and there were certain boundaries and things that I was not OK with being crossed. I didn’t know how to fight that."

Since 'Grey's Anatomy's 2005 premiere, a whole new generation of viewers has become interested in the program. As Katherine continued, "What I find disconcerting is how young those people are that are coming up now. Like, "I don’t think you were alive when we started it."' She was also mistaken as a mother of 'Grey's Anatomy' mother.

Do you know ‘Grey’s Anatomy'?

"I had just had Joshua. I was in the liquor store — I needed some wine. And this man comes up to me and goes, "Excuse me. I’m so sorry, but my daughter, she’s freaking out over here. Would you mind talking to her for a minute?" And I was like, “Sure. Come on over, honey.” She goes, “Do you know ‘Grey’s Anatomy?’” And I was like, “I do. Yeah.” She goes, “Do you know Izzie Stevens?” And I go, “Yes, I do.” She goes, “Are you her mother?” Thankfully that hasn’t happened again. I chose to do that for that scene." Heigl also spoke of reliving her brother's death to film the death of Denny, played by Jeffrey Dean Morgan. "Jeffrey Dean Morgan is a dream to work with. When it got to the point where he dies and she’s laying in the bed with him, I wanted so badly to nail that scene. I wanted it to feel the way it was written on the page."

'I don’t think I’d do it again'

"I don’t like to do that whole. Go into the dark place and listen to the music that’s going to tear my soul apart thing. And the worst was that I really went there. I was 7 when my brother died, but we were in the hospital for a week. I don’t enjoy thinking about that much or that week in the hospital or him in that bed, but I chose to do that for that scene. I don’t think I’d do it again. I don’t think I would put myself in that headspace again to achieve that. I think I would try harder to just act it." she said.