Why Do Some Women Cheat On Their Loved Ones?

In the wake of Kristen Stewart's admission that she cheated on Robert Pattinson, INSIDE EDITION explores why some women cheat when they are in relationships.

The stunning news that Kristen Stewart cheated on her hunky Twilight boyfriend, Robert Pattinson, has everyone wondering - how could such a thing happen?

Emily Morse is a relationship expert on the Bravo show Miss Advised.

Morse told INSIDE EDITION, "She is 22 years old. She is the highest paid actress in Hollywood, she has all of these opportunities right now."

Morse knows what it means to cheat on a boyfriend, she admits that she's done it herself.

"I was no longer interested in the relationship, it was ending, it was sort of a dying relationship. And I met someone and I had a little fling," she said.

It may surprise you to learn that when it comes to cheating, men and women are fairly evenly matched. Polls show 23% of men admit to having cheated on their partners, but 19% of women also say they've cheated.

But men and women don't cheat for the same reasons.

Morse said, "Women tend to cheat more because they are not feeling that emotional connection anymore in the relationship. Either their partner is gone or he is not giving her the reinforcement that she needs. Men cheat because they want more of a sexual variety."

Kristen Stewart's dalliance with director Rupert Sanders appears to be a classic on-set romance. The kind exemplified by the red-hot chemistry between Angelina Jolie and Brad Pitt during the filming of Mr. & Mrs. Smith, which apparently didn't stop when the director yelled, "Cut!"

And now, the question for Stewart and Pattinson is—should he forgive her?

On the INSIDE EDITION website, 70% of our viewers said he should dump her, and that's exactly what he did, according to People magazine.

Morse gave a strong reason for Pattinson allegedly leaving, "His ego said, 'There is no way I am going to be with a woman who cheated on me and is tarnishing my image."

So, can Stewart and Pattinson ever repair their relationship?

Morse said, "If Robert can't feel from the damages over this. If he can't get over the fact that she is with another man, then they will not be able to repair it."