Now married and a father to two children with Mila Kunis, Kutcher has sat down for a revealing interview with actor Dax Sheppard on his new podcast, Armchair Expert.
Kutcher, 40, and Moore, 55, announced their separated in 2011 after six years of marriage, and divorced two years in 2013.
"Right after I got divorced, I went to the mountains for a week by myself," Kutcher said. "I did no food, no drink—just water and tea," he continued. "I took all my computers away, my phone, my everything. I was there by myself, so there was no talking. I just had a notepad, a pen and water and tea—for a week."
As well as closing his relationship with Moore, Kutcher decided it was the right time to shut the door on every past relationship.
“I wrote down every single relationship that I had where I felt like there was some grudge or some anything, regret, anything. And I wrote letters to every single person, and on day seven, I typed them all out and then sent them,” he explained.
"It was like an [Alcoholics Anonymous] exercise. I was like, 'I've probably done some damage.' So I just cleared palette."