Why celebrity couples fail?

Rumors have been tiptoeing around about marriage troubles between Madonna and her husband of seven years, director Guy Ritchie. It seemed to everyone that the once wild, pointy bra-wearing Queen of Pop had settled down for good with her Brit, with her finding Kabbalah, doing massive amounts of yoga, and adopting little David from Malawi. However, all indications point towards a confirmation of a divorce, with word that she's hiring Paul McCartney's divorce lawyer, Fiona Shackleton. Thus, another celebrity marriage bites the dust. Sad, sad, sad. All relationships and marriages face their challenges, but in the world of Hollywood and fame, there are booby traps left and right from being surrounded by gorgeous men and women, having nasty rumors spread, and over publicized romances.

After the jump, pitfalls that celebrity couples face that us average Joe's and Jane's don't have to deal with.

Temptation: the other woman/man
Case in point: Brad Pitt and Jennifer Aniston
Imagine yourself in Jennifer Aniston's shoes: your husband is the hottest man alive and he's leaving to shoot a movie with the hottest woman alive, Angelina Jolie. The set of Mr. and Mrs. Smith proved to be too much quality time between Brad and Angelina and those pouty lips were no match for Jen's toned arms. Temptation abounds in the sea of endless beauty that is Hollywood.

Over-publicity
Case in point: Ben Affleck and Jennifer Lopez
There was a time in 2002 where you couldn't turn on the TV or read a magazine without seeing or hearing that dreaded, stupid compound word, "Bennifer." They were the ultimate publicity whores, which probably was the end cause of their broken off engagement. The couple was overexposed in a bad way, resulting in the embarrassing, box office failure, Gigli. No wonder both J.Lo and Affleck try to keep a low profile with their now husband and wife, Marc Anthony and Jennifer Garner.

One is more famous
Case in point: Reese Witherspoon and Ryan Phillippe
Reese Witherspoon is America's darling. She was charming and hilarious in Legally Blonde and won an Oscar for her portrayal of June Carter in Walk the Line. Her husband...er, what's his name? Exactly. Ryan Phillippe was suffering from a severe drought of good movie roles, and little fame. Perhaps he felt neglected and emasculated? Whatever the real issue was, he cheated on her with actress Abbie Cornish and the World's population collectively thought: downgrade.

Overexposed by Reality TV
Case in point: Jessica Simpson and Nick Lachey
They were like the Lucille Ball and Desi Arnez of the millennium, except she was the wacky blond and he was the straight laced boy next door. Neither one of them was very famous before the run of their reality show Newlyweds, that documented their marriage, showcasing her ditziness and his good guy demeanor. It really catapulted Simpson to celebrity status, inflated her ago, and resulted in her leaving poor Nick. Another couple gone bad due to reality TV: Travis Barker and Shanna Moakler in MTV's, Meet the Barkers.

Are celebrity couples doomed to fail because of the nature of the industry they work in? How would it be possible to avoid these pitfalls?