“I’m surprised at the reaction,” the 60-year-old actress — who revealed the affair in the new issue of PEOPLE, which contains an excerpt from her new memoir The Princess Diarist — admitted during an appearance on the Today show Monday morning. “I don’t think it is that surprising.”
Fisher writes about the romance, which happened when Fisher was just 19 and Ford was a married 33-year-old father, in The Princess Diarist. The new book comes after Fisher rediscovered old diaries written while she was shooting the movie, in which she played Princess Leia to Ford’s Han Solo.
Fisher says that finding the journals brought back old memories, as she admittedly doesn’t “remember any details.”
“I had forgotten that I’d written them, and I’ve never written diaries sort of like that,” she said. “I write when I’m upset … it was about two or three months of upset.”
Fisher added, “It was sad because I was so insecure, and it’s very raw and obviously I didn’t expect anyone — including myself, I suppose later on — to read it.”
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The actress said she felt terrible about having an affair with a married father of two and carried that guilt with her for years after the romance ended.
“I wasn’t raised that way,” she said. “But when you’re on location — this is something I discovered — everything is permitted.”
Fisher said she warned Ford about coming forward with the news, but after all their years of friendship, he made light of the situation.
“He’s incredible private,” she said. “I feel really bad about doing that to him. But yes, I told him I found the journals and I was going to publish them, and he sort of went, ‘Lawyer!’ “
Fisher previously spoke to PEOPLE exclusively about the “intense” off-screen romance.
“It was Han and Leia during the week, and Carrie and Harrison during the weekend,” she said.
For much more from Fisher — and to read the exclusive excerpt of The Princess Diarist— pick up this week’s issue of PEOPLE, on newsstands now.