Carrie Fisher finds it "surprising" that the story of her former fling with "Star Wars" co-star Harrison Ford has garnered so much attention.

In her new memoir, "The Princess Diarist," Fisher writes that she began an "intense" affair with Ford in 1976, when he was 33 and she was 19, that went on for several months while they were filming the beloved sci-fi movie.

On Monday's "Today" show, Fisher told co-anchor Savannah Guthrie that she gave Ford a heads up that she would be sharing details of their alleged romance in her book. "He's incredibly private," she said. "I feel really bad doing that to him."

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When asked if she was in love with Ford at the time of their romance, Fisher responded, "Well, I was 19. So, yeah. I was not sort of a cavalier-type person."

She also writes about being relieved when the alleged affair ended with Ford, as he was married Mary Marquardt with two children at the time. "I wasn't raised that way," Fisher told Guthrie. "But when you're on location, this is something I discovered, everything is permitted. I didn't know that. I haven't been on location since."

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Fisher's book is made up of "forgotten" journal entries she made during her time portraying Princess Leia. The actress admitted that it was "sad" to go back and read her diary because she was "so insecure" back then.

"It's very raw," she explained. "Obviously I didn't expect anyone, including myself, to read it."

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