Shirley MacLaine says her marriage lasted 28 years because it was open

By Sarah Walker

Before you turn to a therapist or marriage counsellor for relationship advice, one of Hollywood's most enduring stars, Shirley MacLaine, has doled out some life lessons of her own - and they may come as a surprise.

The redheaded actress shared her candid and pragmatic opinion on coupledom during a recent Sirius XM town hall. Her advice on how to make a partnership last? Sleep with other people.

Shirley MacLaine stopped by SiriusXM Studios on Mar. 15.

"I guess you would say [we] 'practiced an open marriage' in 1954, which was another lifetime," she says of her 28 years with film producer Steve Parker. "No one understood it, we did. He lived in Japan basically, I lived in America working, and this and that."

Though the duo split in 1982, she says they were the best of friends.

"I would say [it was] better to stay friends... I was very open about all of that and so was he... I think that's the basis for a long-lasting marriage, if you really want to do such a thing."

Read More: Famous couples with big age gaps

According to the Daily Mail, the 81-year-old Downton Abbey star took several lovers while married, including comedian Danny Kaye, singer Yves Montand and actor Robert Mitchum.

She and Steve went on to have one daughter together, actress Sachi Parker.

Shirley and her husband Steve Parker in 1964.

Today, Shirley admits she's happier on her own. "I'm having a relationship now, that is teaching me about possessiveness with intimacy and it's with my three dogs. I adore my dogs," she says. "And I've had to get a dog nanny/food lady for the dogs because I've been working so much."

The star's radio appearance was, in part, a promotion for her new book Above the Line.

Don't miss a beat with HELLO! Canada's Daily Hits newsletter, your daily dose of royal and celebrity news, fashion, weddings and more. CLICK HERE to sign up for free!