Oprah, John Tesh Oprah, John Tesh

Oprah Winfrey and John Tesh were romantically involved until he walked out on her, biographer Kitty Kelley says.

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According to an excerpt from Kelley's upcoming Winfrey biography in the New York Daily News, Tesh and Winfrey shared her Nashville apartment in the '70s until he abruptly left. They both had TV jobs in Nashville at the time.

Kelley also claims the "social pressure" of the couple's interracial relationship at the time was too much for Tesh.

"He said one night he looked down and saw his white body next to her black body and couldn't take it anymore," one of Tesh's unnamed ex-girlfriends told Kelley. "He walked out in the middle of the night. ... He told me he later felt very guilty about it."

Winfrey's spokesman declined to comment; Tesh's rep did not immediately respond to a request for comment.

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The book, which comes out Tuesday, already is No. 19 on Amazon's best-seller list.

Tesh, a Grammy-nominated musician who hosted Entertainment Tonight from 1986 to '96, is married to actress Connie Sellecca, while Winfrey is still with longtime boyfriend Stedman Graham.

Kelley, whose credibility often has been questioned, is best known for her unauthorized biographies of celebrities and politicians including Frank Sinatra, Nancy Reagan and Elizabeth Taylor.