Carrie Fisher Explains Why She Went Public With Harrison Ford Affair While Making bintang Wars 

Carrie Fisher came across journals she kept during her three-month affair with Harrison Ford while filming the original 

 in 1976, she figured the time for secrecy was over.

“It’s been 40 years!” the actress-author, 60, tells PEOPLE of including their whirlwind romance in her new book, The Princess Diarist, excerpted exclusively in this week’s issue.

“I didn’t say anything to anybody for years but it’s not like anyone’s deeply affected by it anymore.”

Whether Ford, a 33-year-old married father of two at the time, will agree remains to be seen. Fisher did give the actor (who didn’t respond to PEOPLE’s request for comment) a friendly heads-up and even sent him a draft — but she doesn’t know if he’s even read it.

“I would never want to embarrass him,” says Fisher, who was 19 when the two got together. “I was so inexperienced, but I trusted something about him. He was kind.”

Still, Fisher feels the statute of limitations on their secret had run its course.

“Harrison’s very private, but I think I waited an appropriate amount of time,” she says. “How much longer could I wait?”

For much more from Fisher – and to read an exclusive excerpt of The Princess Diarist – pick up this week’s issue of PEOPLE.

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