Looking back, Simpson says she "disrespected" the host and her fans.
Jessica Simpson opened up about her battle with alcohol and pills in her new memoir, "Open Book," admitting there's one interview she did during that struggle she "had no business" doing.
In 2017, the singer appeared on "The Ellen DeGeneres Show," leaving the host looking at her -- and the camera -- in disbelief and fans wondering if she was drunk at the time.
"I went on The Ellen DeGeneres Show to promote the Collection, making an appearance I have never watched," Simpson wrote in her book. "I admit I drank beforehand and was also on steroids for a chest infection that made me hoarse."
"I was nervous, but I'd always been able to turn it on for talk shows," she continued. "Instead, I couldn't find Ellen’s rhythm, mumbling and second-guessing everything I was saying. At first, Ellen tried to help, and then she gave up. Her blank stare at my conversational freefall was tough love."
Simpson said Ellen "didn't say anything" to her after the interview. "I awkwardly walked off the stage and took in the look on the face of my publicist and friend Lauren. 'Uhh,' she said."
"You could have done better," her publicist said, something Simpson noted was "probably the most critical thing this kind woman has ever said to me."
Addressing the host and her fans, she also wrote, "I want to say it here to Ellen and the viewers: I'm truly sorry. I disrespected them by trying to make an appearance when I had no business doing so."
After hitting rock bottom in October that same year, Simpson has been sober for over two years.
Her memoir, "Open Book," is out now. See more TooFab coverage below!