For Hollywood Couples, Distance Might Make All the Difference

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At the height of his real-life "Gossip Girl" romance with co-star Blake Lively, Penn Badgley told Parade Magazine, "Blake and I have been able to make our relationship work because we're both having success in a tough business. There's zero competition or jealousy."

On Wednesday, a rep for both stars – their "Gossip Girl" counterparts Serena van der Woodsen and Dan Humphrey were also romantically involved – confirmed to People that the couple, who began dating in 2007, have called it quits.

Does spending too much time together both on the set and off the set portend potential disaster for celebrity-couple relationships?

VIDEO: David Arquette explains reasons for his separation to Courteney Cox.Play

Excess proximity can indeed be debilitating, especially considering what David Arquette had to say. After 11 years of marriage, Arquette and Courteney Cox recently announced their separation. Speaking Wednesday on Howard Stern's Sirius XM radio show, Arquette said he hoped that some space might help their relationship. "We gotta kind of make this separation more separate," he said. Later in the interview, he said, 'You keep it like that and maybe she'll miss me more or whatever."

Courteney Cox and David Arquette.

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Arquette may indeed be on the right track.

"Most people fantasize that it's great to spend a lot of time together, but in reality, people are not made to be together all the time – there needs to be a certain limit," said Michael Mercer, an organizational psychologist with an expertise in relationship issues, and president of the Mercer Group, in Barrington, Ill.

Billy Ray Cyrus and Tish Cyrus spent more than 17 years together as parents and career steerers to their superstar daughter, Miley. "Everything is about keeping her grounded," Tish Cyrus told People magazine in 2007.

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But it seems they too needed space. The Cyrus' announced last week that they're divorcing, saying in a statement, "As you can imagine, this is a very difficult time for our family. We are trying to work through some personal matters. We appreciate your thoughts and prayers."

Mercer likens too much together-time in a relationship to finding a food you like, and then eating it incessantly. "Too much of something often leads to taking it for granted and becoming bored," he said.

"These are couples who spend nearly every waking minute together, with long hours on the set, seven days a week," said Jennifer Garcia, an assistant editor at People. "It puts stress on a relationship."

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Garcia noted that Dave Annable and Emily VanCamp, actors on "Brothers and Sisters," were also an off-screen couple who eventually broke up.

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"The fact that two stars work together doesn't ensure the demise of a romantic relationship, but the situation makes a relationship incredibly difficult to sustain," noted Garcia. "Couples who make it work – Kristen Stewart and Robert Pattinson, and Susan and Robert Downey Jr. come to mind – succeed because each person in the relationship has breathing room."

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Cheryl Gerson, a licensed clinical social worker in private practice in New York, who has an expertise in relationship issues, said that privacy is critical. "Being in relationship means you always have a consciousness of the other person, and so you may not have the opportunity to be simply yourself," she said. "Even when these couples are spotted walking leisurely in public, they are still 'on stage.'"

People reported that Lively, starring in "The Town," and Badgley, starring in "Easy A," had both attended the Toronto Film Festival in September, where they each promoted their new films, but that scheduling conflicts kept them from each other's premieres. "Unfortunately, her premiere is, like, right now, otherwise, we would be at each other's," Badgley told People.

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To some experts, this type of behavior might even be perceived as co-dependency.

Describing too much time together as being potentially "smothering," Bonnie Jacobson, a clinical psychologist in private practice in New York, who has a specialty in relationship issues, noted that one partner in the relationship might be dependent, which could lead to incessantly checking on the other partner, leading to feelings of being watched and controlled.

"When you work together, it's even more essential to have time alone," said Jacobson.

With the benefit of hindsight, Badgley's comment to Parade is telling.

"Everybody needs attention," Badgley said. "It helps to have someone by your side."

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Now, maybe, not so incessantly as before.