Winfrey tirelessly campaigned for Obama during his first presidential run in 2008. In return for her support, the New York Post said Winfrey was promised tremendous access to the White House, if Obama won, and exclusive material she could use for programs on her OWN network.
"Oprah intended to make her unique White House access a part of her new network," the newspaper quoted a source close to Winfrey as saying. "There were big plans, and a team was put together to come up with proposals that would have been mutually beneficial. But none of that ever happened. Oprah sent notes and a rep to talk to [senior adviser] Valerie Jarrett, but nothing came of it. It slowly dawned on Oprah that the Obamas had absolutely no intention of keeping their word and bringing her into their confidence."
The Post said Winfrey then declined the first couple's request to help promote the Affordable Care Act -- nicknamed Obamacare -- as well as other initiatives.
Post contributor Edward Klein's 2012 book "The Amateur" claimed Obama's wife Michelle was jealous of Winfrey because he sought her advice.
"For her part, Oprah doesn't like being with Michelle, because the first lady is constantly one-upping the president and anybody else around her," a Winfrey adviser is quoted as saying in the book.
"Oprah has struck back by banning the Obamas from her O, The Oprah Magazine. ... It probably hurts Oprah more than Obama, who, if he had his head screwed on straight, would have flown to California and begged Oprah to help him save Obamacare.
But Obama hasn't budged, and neither has Oprah. She's hurt and angry, and I seriously doubt that Oprah will ever make up with the Obamas. She knows how to hold a grudge."