"6 people who know me well have called today congratulating me or surprised they weren't invited to my wedding," she wrote on Twitter Monday. "IT'S NOT TRUE!!"
The couple has been dating since 1986. Graham, 65, proposed to Winfrey, 62, in 1992 and they planned to get hitched a year later.
"The moment he asked me to marry him I was like, 'Oh God, now I actually have to get married?'" she recanted during a 2015 Super Soul Sunday interview with TV producer Shonda Rhimes. "What I realized is, I don't want to be married, because I could not have the life that I created for myself. I couldn't do it."