Speaking on ITV's Lorraine, eliminated rapper Honey G, 35, had nothing but praise for Mrs O, who tried to save her during Sunday's sing off but was unsuccessful.
Honey G said: "She is probably one of the most unbelievable people I've ever met. I said to her last night, nobody in my whole life has ever stuck up for me the way she did last night on the panel when the judges were ready to make their decision."
Sharon had desperately tried to convince Simon Cowell and Nicole Scherzinger to save Honey G, but they decided to back Louis Walsh's act 5 After Midnight.
"I'll never forget how good Sharon's been to me," added Honey G. "She even sent me a message last night saying that's it now, we're friends for life."
The rapper also praised Sharon on Sunday night's Xtra Factor, saying: "I am just so honoured and humbled that Sharon Osbourne has got behind me and supported me throughout the whole X Factor journey.
"I have Sharon behind me, backing me. She knows me. Simon once said that Sharon and I are like two peas in a pod. And we are. We get on so well. She knows where I want to take my career as a rap artist, she sees my vision, she gets me, she understands me. I don't think any other judge could have done a better job.
"I promised Sharon a private jet and she will get one!"
X Factor continues Saturday at 8pm on ITV with Christmas Week.