Carrie Fisher's November 15 admission that she and Star Wars co-star Harrison Ford had an affair on the movie's set left longtime fans shellshocked. Still, in an interview with Today this morning (November 21), Fisher insisted she doesn't quite understand why the news has become such a big deal.

"I'm surprised at the reaction, that it's so much," Fisher said. "I don't know, I don't think it's that surprising. A lot of fans did think about it for awhile and they made up 'Carrison' as a word...'Is Carrison real?' So that was going on for awhile."

"[I'm surprised] it seems like it would be so improbable," she added. "We were cast that way."

Fisher said she was inspired to release new book The Princess Diarist after stumbling across old journal entries she'd written while filming Star Wars, and that she'd forgotten how differently she used to see things. These days, she said, she usually only writes while upset or depressed.

"I was 19, I was not sort of a cavalier person," she said. "[But] it was sad, because I was so insecure and it's very raw. Obviously, I didn't expect anyone, including myself later on, to read it."

And though Fisher's said she's got no guilt about bringing her former romance to light, she does hope it doesn't put Ford in a tough spot. At the time of the affair, he was married and had two children.

"He's incredibly private," she said. "I feel really bad about doing that to him."

"I wasn't raised that way," she added. "But when you're on location — this is something I've discovered — everything is permitted. I didn't know that."

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