Ask a celebrity what the key to a successful career is and you'll probably get some out-of-touch answers. After all, a person who has benefitted from an abnormal amount of luck is often not the best at dispensing actionable advice.

However, no level of fame makes marriage any easier. In fact, skyrocketing status often stresses a partnership.

This might be why finding out your favorite A-lister has been married for decades is both surprising and heartening. And also why celebrities who have been together pre- and post-success have some helpful tips for maintaining a happy union.

Here are five actors, entrepreneurs, and authors on what they believe is the key to a successful marriage.

Barbara Corcoran: Set boundaries

For multi-millionaire Shark Tank judge Barbara Corcoran the key to a long-lasting marriage is respecting your partner's personal space.

Corcoran and her husband, Bill Higgins, have been married more than 35 years and have never shared a bedroom.

"I've had a separate bedroom with Bill for like 40 years," Corcoran said on the Today Show. "I have to invite him in — he invites me in occasionally."

After a long day of work Corcoran says she needs time to recharge.

"I think there's something to be said about your own private space," she told People. "I lead a very busy life. I have a huge family that I'm always entertaining. I have very sincere, active friends and so what I need more than anything else is a respite, and my husband is not relaxing."

Deepak Chopra: Give up being right

Deepak Chopra's expertise spans a wide range of physical and mental topics: mediation, nutrition, mindfulness.

But Chopra, 78, also has some acute insights on marriage. After all, he has been in one for more than 50 years. 

His secret to a long marriage? 

"I have only one tip for healthy, long-term relationships," he says. "Ask yourself, 'Do I want to be happy or do I want to be right?' Give up being right and your relationship will thrive forever." 

Ina Garten: Take space... and go to therapy

In her memoir "Be Ready When the Luck Happens," Ina Garten, 77, revealed that she and her husband Jeffrey almost got a divorce. In fact, they separated at Garten's request for a brief period of time in the 1970s.

The rift started when Garten bought a specialty food shop in Westhampton, New York. While Jeffrey was supportive of her ambitions, he also expected her to fit the traditional wife role, she writes in her book.

"I'd be the wife, responsible for everything domestic, and Jeffrey would be the 'man' who helped occasionally," she writes. "It wasn't the stupid chores that bothered me; it was the feeling that I wasn't an equal partner."

Eventually, she asked for a separation.

Jeffrey respected her wishes and the two parted for a summer. When they reconnected, he asked if there was anything he could do to reconcile, to which she responded "therapy."

He went the very next day — and it saved their marriage.

Jason Alexander: Don't judge them on their worst day

In "Seinfeld," actor Jason Alexander plays Jerry's neurotic, albeit lovable, friend who is shoddily employed and constantly fumbling romantic courtships. While filming the show, Alexander's love life was panning out quite differently.

The actor was happily married to his wife Daena Title, and has remained so for more than 40 years. Recently, Alexander opened up about the key to their long-lasting union.

"I'm married to a woman who lives this thing that I first heard of in 'A Raisin of the Sun,'" he said on the Today Show. "It's kind of quoted there, but she does it. It goes something like this: On my worst day, she remembers me on my best day and beckons me back."

He continued on to say, "If you have a partner who can do that, because we all have worst days, you don't give up on that partner."

Jay Leno: Remember that most fights aren't worth it

Jay Leno may be known for his affinity for cars — his auto collection includes over 100 vehicles — but his biggest commitment is to his wife of 38 years, Mavis.

In a 2019 Q&A interview with The Wall Street Journal, Leno said, "I always tell people that you should marry the person you wish you could have been. That's a pretty good goal."

He says he's learned a key lesson: "The secret to a long marriage is realizing there's nothing really worth fighting about."

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