'X Factor' mentor Sharon Osbourne has opened up about being away from her children, Jack, Kelly, and their older sister Aimee, while they were young in order to maintain a career and lifestyle and described it as a mistake. 

Speaking to UK chat show host Graham Norton, which airs tonight (November 29), Osbourne confessed that she regrets their time spent apart and knows she will never be able to get it back:

"We both worked to continue a lifestyle we had become accustomed to and we had to travel so my kids spent quite a time away from us and you can never get that time back. It was the biggest mistake I ever did, but would I have wanted to live a lesser life? You make the most of what you have. I don't know how, but Jack and Kelly came out just great."

She also spoke about her husband, Ozzy Osbourne, and his recent relapse with drugs and alcohol, adding: "It was the combination of drugs and drink and it was like, 'No, not again,' so I moved out. We are back together and it is all down to him, he is on the 12 steps and he is clean and sober."

"He stopped because he knows what he was going to lose, not just me but everything. He says we're like bread and butter. We fit together so perfectly. We are a team and the hardest thing I ever had to do was walk away."