Oprah Winfrey says she has no regrets regarding her life.

The billionaire mogul opened up about why she decided not to marry her longtime partner in the PEOPLE celebrating Women Changing the World issue.

Winfrey met Stedman Graham in 1986 at a charity gala. At one point in her relationship, she thought of becoming a mom, Oprah told PEOPLE.

“At one point in Chicago I had bought an additional apartment because I was thinking, ‘Well, if we get married, I’m going to need room for children,’” Oprah said.

However, during her years on The Oprah Winfrey Show, she changed her decision after seeing “the depth of responsibility and sacrifice that is actually required to be a mother.”

“I realized, ‘Whoa, I’m talking to a lot of messed-up people, and they are messed up because they had mothers and fathers who were not aware of how serious that job is,’” Oprah said.

“I don’t have the ability to compartmentalize the way I see other women do.

“It is why, throughout my years, I have had the highest regard for women who choose to be at home [with] their kids, because I don’t know how you do that all day long. Nobody gives women the credit they deserve.”

She continued: “I used to think about this all the time, that I was working these 17-hour days, and so were my producers, and then I go home and I have my two dogs and I have Stedman, who’s letting me be who I need to be in the world.

“He’s never demanding anything from me like, ‘Where’s my breakfast? Where’s my dinner?’ Never any of that, which I believed would have changed had we married.”

“Both he and I now say, ‘If we had married, we would not be together,’” Oprah added.

“No question about it — we would not stay married, because of what that would have meant to him, and I would have had my own ideas about it.”

And she has firmly stood by this decision.

“I have not had one regret about that. I also believe that part of the reason why I don’t have regrets is because I got to fulfill it in the way that was best for me: the Oprah Winfrey Leadership Academy for Girls in South Africa,” she said.

“Those girls fill that maternal fold that I perhaps would have had. In fact, they overfill — I’m overflowed with maternal.”