Kristen Stewart issues public apology to Robert Pattinson after cheating with married director

Kristen Stewart has come clean about cheating on Robert Pattinson – and she is publicly apologizing to her long-time boyfriend for her indiscretion.

[Related: Who is Rupert Sanders? 5 things to know about the director]

"I'm deeply sorry for the hurt and embarrassment I've caused to those close to me and everyone this has affected," Stewart, who was photographed kissing her married "Snow White and the Huntsman" director Rupert Sanders, said in a statement to People. "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."

On Tuesday night, Us Weekly broke the news about Stewart's cheating scandal, posting the cover of its latest issue featuring a photo of Stewart, 22, kissing Sanders, 41. The photos were taken earlier this month during what the magazine has called a “series of steamy rendezvous in L.A.”

Sanders – who like Pattinson is British – directed Stewart in “SWATH.” While talking about what it was like to work with her, he said, “She's tenacious and rebellious and really kind of raw and primal. She was kind of a wild horse – [and I was] trying to rein her down. She has that kind of modernity that I wanted for Snow White. She's not sitting waiting for the prince to come."

[Related: Snow White & the Huntsman: trailer and cast (watch)]

Interestingly, Sanders’ wife, model Liberty Ross, also appeared in the film – as the mother of Stewart’s character. Ross tweeted a photo of herself with Stewart at the premiere. Yesterday, just as news of Stewart and Sanders’ affair broke, Ross tweeted a famous quote from Marilyn Monroe, who knew a little something about cheating scandals, writing, "Sometimes good things fall apart so better things can fall together.” That post was followed by a single word, “Wow,” and then Ross deleted her account soon after.

Following Stewart’s apology, Sanders issued one of his own. "I am utterly distraught about the pain I have caused my family," he said in a statement to People on Wednesday. "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."

Stewart and Pattinson, 26, have been a couple since 2009 – soon after they met on the set of “Twilight.” Initially press shy about discussing their relationship or showing any PDA, they’ve been more public in recent months. At the Cannes Film Festival in May, they were openly kissing at a party. Earlier this month they were all smiles sitting next to one another a Comic Con. And most recently, the couple was spotted together on Sunday at the Teen Choice Awards. While on stage collecting their surfboard trophies, they whispered intimately to one another.

No word from Pattinson’s camp as to whether or not he has accepted this very public apology, but in an April interview for Italian Vanity Fair he had strong opinions about infidelity. "But there's a thing I've never got: That is, why do people cheat?” he asked. “I can understand the impulse. But not how you can keep two relationships going at the same time for long … I'm not the casual-affair kind of guy. If I choose to be with someone, it's because I really want it. When I have a relationship, I'm 100 percent into it."

One thing is for sure, Stewart and Pattinson will be spending a lot of time together over the next few months. “Breaking Dawn – Part 2” will hit theaters on November 16 and the two are scheduled for a global publicity tour to promote the movie.

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