Appearing on "The Howard Stern Show," O'Donnell said she wrote a letter to Cohen on the night Trump was impeachment by House Democrats in December 2019.
"I said, 'I can't help but find myself thinking about you there in jail, you who's from Long Island who sounds like everybody I grew up with, you who's near my age, you are the guy who's paying for what this man did. And it seems horrifically unfair,'" O'Donnell said she wrote to Cohen. "And he wrote back to me and said, 'I can't believe you're writing me. I have such guilt over the way I participated, you know, with Trump.' And so we became pen pals. And then I went to the prison to visit him."
O'Donnell, who had a long-lasting feud with Trump long before he entered politics, told Stern that she got to ask Cohen "every question I had" during her visit to the prison, which took place before the coronavirus outbreak forced the country into quarantine.
"I thought I'd be up there for, like, an hour. I was there for six and a half hours talking to him," O'Donnell said.
The comedian said Cohen apologized to her for "every bad name" that he and Trump came up with, saying: "Michael ran that show for 15 years. He really did. He was the fixer and the thug and he was the guy who implemented the attacks on everyone. It was him."
"But physically, he looks good. He looks thin, he looks fit, he looks rested -- believe it or not," O'Donnell told Stern. "He's so remorseful and so upset with himself for not listening to what his wife and children were saying to him for years. You know, I didn't realize he had a huge, successful business before he went to Trump. He had made all of his money and was in semi-retirement. And then Trump asked him to do it."
"And I'm like, 'Why did you do it?' And he goes, 'I don't know. I felt like I was going to get to be, like, the big guy in the midst of things, you know.' And then I said, 'You ended up having to do horrible things for him.' And he was like, 'Yes and I regret every single one.'"