Kristen Stewart is in the news for all the wrong reason. It was revealed last night that she had cheated on "Twilight" co-star and boyfriend Robert Pattinson with her married director Rupert Sanders. The 22 year-old actress was pictured in the arms of Sanders, who directed her latest film "Snow White and The Huntsman".

It seems that Stewart is regretting her liaison with Sanders, and issued a public apology on her infidelity. "I'm deeply sorry for the hurt and embarrassment I've caused to those close to me and everyone this has affected," Stewart said, according to People.

She continued: "This momentary indiscretion has jeopardized the most important thing in my life, the person I love and respect the most, Rob. I love him, I love him, I'm so sorry."

Sanders, 41, who is married to Liberty Ross and have two young children together, also issued an apology. He told People: "I am utterly distraught about the pain I have caused my family. My beautiful wife and heavenly children are all I have in this world. I love them with all my heart. I am praying that we can get through this together."

Sanders' wife Liberty played the role of "Queen Eleanor", Stewart's mother, in the "Snow White and the Huntsman", which was only released last month.

The affair was unveiled Tuesday by Us Weekly magazine which claims to have photographs of the two hooking up and not having "enough" of themselves.

Stewart, 22, and Rupert Sanders, 41, were caught by a photographer last week in what seemed to be a passionate date.

Stewart is reportedly "devastated" for what she did, according to People Magazine.

"Kristen is absolutely devastated," a source told People. "It was a mistake and a complete lapse in judgment." "She wasn't having an affair with Rupert. It was just a fleeting moment that shouldn't have happened," the source added. "She never meant to hurt anyone. She's a good person who just made a bad choice."

Stewart's fans were disappointed with the infidelity claims. One disapproving fan tweeted: "Kristen Stewart, how could you cheat on Robert Pattinson with a married man that has children? So disappointed in you."