The iconic actress opens up about the secret to her long-lasting marriage
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Ann-Margret says by the third date with her husband, 77 Sunset Strip star Roger Smith, she knew he was the one.

“I knew he would protect me. I knew that I could depend on him. I sensed it completely,” she tells PEOPLE.

On May 8, the couple will celebrate their 50th anniversary, and Ann-Margret, 75, says the secret to their long-lasting relationship is laughter.

“We laugh at ourselves. We get into weird situations. If you can’t laugh at yourself you are in trouble. We laugh before everyone else does,” she says of Smith, 84.

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Yet, on their wedding day in 1967, the Swedish-born actress, who previously dated Elvis, was doing more crying than laughing. The couple eloped to Las Vegas, and Margret says the room they exchanged vows in was filled with cigarette smoke and far from glamorous.

“This is not the way I envisioned my wedding,” she says. “I think everyone thought I was pregnant because I was crying though the whole thing. But we did it!”

The couple have also had their share of ups and downs, including her near-fatal fall from a 22-ft. platform while performing in 1972 — and his 1980 diagnosis of myasthenia gravis, a nerve-and-muscle disorder.

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But the Swedish-born singer and actress, 75, who will next be seen in the heist comedy Going in Style, says there is another reason why they have stayed together so long.

“It’s very simple actually,” she says. “We both want it to work.”