Twenty years ago, Melania walked out on Donald Trump and broke up with him, according to the author of a new tell-all about the president.

The blockbuster revelation comes in a new book, The Trump White House: Changing the Rules of the Game by former Washington Post reporter Ronald Kessler.

He claims it happened in 1998. At the time Melania and the future president had only been dating a few months, but it was already serious.

Melania had even moved into Mar-a-Lago, but in the midst of the relationship, Trump reconnected with an old flame and his girlfriend caught wind of it.

"She found out that Trump had seen Kara Young, a former model he dated, and she broke up with him,” the author claims. “She didn't care about the billions. She said goodbye. She ordered her clothes sent from Mar-a-Lago."

The breakup, however, did not last long.

"A week later, he wooed her back and she sent her clothes back to Mar-a-Lago," Kessler claims.

Now, despite accusations that Trump has had extramarital affairs with Stormy Daniels and Karen McDougal back in 2006, which the president denies, Kessler says all is well in the marriage.

"That marriage is going to last," Kessler told Inside Edition.

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