Bennifer, Brangelina go bust: how 'egos clashing' and 'struggle for dominance' can kill Hollywood marriages

Relationships are hard. 

And when both partners are A-list celebrities, it can add even more pressure. 

After ending their engagement 20 years ago and marrying other people, Ben Affleck and Jennifer Lopez thought they had reunited for their happily ever after. Their love burned hot, but appears to have quickly gone down in flames. Although they have not spoken publicly about it, they spent much of the summer on separate coasts, and a source tells Fox News Digital, "They are done. Totally done. They are not getting back together."

But Lopez and Affleck aren’t the only power couple to fall apart. Brad Pitt’s marriages to both Jennifer Aniston and Angelina Jolie ended in divorce, as did Meg Ryan and Dennis Quaid’s matrimony, and Nicole Kidman and Tom Cruise's union. 

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The marriages of Brad Pitt and Angelina Jolie, and Ben Affleck and Jennifer Lopez, both faced struggles. (Getty)

"When two A-listers enter into a long-term relationship, there are unique challenges that come into play that initially can be overlooked," Alessandra Conti, celebrity matchmaker for matchmakersinthecity.com, told Fox News Digital. 

"When stars come together, it can seem like it's straight out of a movie; their chemistry is palpable, the paparazzi are hooked on their every move, the glamour and intrigue of it all is intoxicating and quite profitable for whatever projects they happen to be working on at the moment. The illusion of perfection is often just like a lot of Hollywood — smoke and mirrors."

Nicole Kidman and Tom Cruise divorced in 2001. (Leonardo Cendamo/Getty Images)

Pitt and Aniston married in 2000, but just five years later they were filing for divorce. He quickly moved on with Angelina Jolie, his costar in 2005's "Mr. & Mrs. Smith." The couple eventually married in 2014, but have been locked in a messy divorce battle for years. 

Conti, who has been a matchmaker for more than 12 years in Hollywood, added, "I have a saying that in every relationship, there is a diamond and there is a setting. Two diamonds are not an ideal match because when there are two powerful personalities in a relationship, especially when they are in the entertainment industry, a major power struggle can ensue."

She said while there are "fireworks" in the beginning of the relationship, that’s not sustainable. 

Brad Pitt was married to Jennifer Aniston before Angelina Jolie. (Kevin Winter/Getty Images)

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"Fireworks are exciting — however, they are typically a red flag if a client is looking for their lifelong love match," Conti said. "The passion and fire that is synonymous with these superstar romances can erode into egos clashing and a struggle for dominance."

Damona Hoffman, celebrity dating coach and author of "F the Fairytale," told Fox News Digital that it’s not as much about the couple’s A-list status but rather relentless schedules "and the pressures of a job in the spotlight."

"This is why we also see the same phenomenon with high-profile people in business," Hoffman said, naming people like Jeff Bezos and Bill Gates. "Two successful Hollywood careers means lots of time on the road apart, grueling hours and many people on the team managing your every move. The best way to make it work is to look at each person's career as having seasons in which they take the spotlight while the other person focuses more on the home front and supporting their partner."

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Blake Lively and Ryan Reynolds are a "good example of a couple who support each other’s careers."  (Mike Coppola/Getty Images)

Hoffman said Blake Lively and Ryan Reynolds are a good example of a couple who support each other’s careers, taking turns in the spotlight. "These two also have a great sense of humor with one another and make a point of publicly supporting each other, which is key to long-term success," she said.

"Ryan Gosling and Eva Mendes are also great relationship role models," Hoffman added. "When Ryan was having a moment in his ‘Ken’ era, Eva was supporting him behind the scenes, but never tried to take the spotlight from him. When celebrity couples get too competitive with one another, that can spell disaster. When they can support one another through the highs and lows of being a celebrity, they can stand the test of time."

A relationship expert called Eva Mendes and Ryan Gosling "great relationship role models."  (Sonia Recchia/Getty Images)

"Their particular job or public role doesn't matter. It's all about finding compromise and making sure your partner knows that you love them more than fame and fortune," she noted.