Robert Pattinson and Kristen Stewart are one of our favorite celebrity couples. We’ve loved watching them in love, on-screen and off, so much that this latest news on their relationship is devastating: Kristen allegedly cheated on Rob.

People reports that Kristen, 22, had a “brief fling” with Rupert Sanders, the married director of her recent film Snow White and the Huntsman. “Kristen is absolutely devastated,” a source tells the magazine. “It was a mistake and a complete lapse in judgement.”

“She wasn’t having an affair with Rupert. It was just a fleeting moment that shouldn’t have happened. She never meant to hurt anyone. She’s a good person who just made a bad choice,” the source says. The source alleges that the tryst occurred not when Kristen and Rupert were filming, but recently.

In a separate report, Us Weekly claims the encounter happened July 17 in Los Angeles. According to them, the two were caught by photographers in what is being referred to as a “marathon make out session.” One photographer told the magazine, “It seemed like they couldn’t get enough.”

Rupert, 41, who is married to British Vogue model Liberty Ross, 33, has two children, ages 7 and 5.

Filming on Snow White and the Huntsman began in August of 2011 and wrapped in December, with the film having been released this past May. We have to wonder if this is something that began months ago, when Kristen and Rupert were working together for those four months, or if it truly is a recent development, as People claims.

Rob and Kristen have been together for the past four years, since meeting each other on the set of the first Twilight film. The two even live together. While we don’t know Kristen’s stance on cheating, Rob has been very vocal about how he’s against cheating, even saying how he doesn’t understand it.

滬江娛樂快訊：據(jù)最新一期的《美國周刊》報道，羅伯特·帕丁森(Robert Pattinson，26歲)女友克里斯汀·斯圖爾特(Kristen Stewart，22歲)和《白雪公主與獵人》(Snow White and the Huntsman)導演魯伯特·山德斯(Rupert Sanders，41歲)親密約會的照片被曝光。

據(jù)悉，山德斯為已婚人士，他的妻子是英國《Vogue》雜志模特麗波緹·羅斯(Liberty Ross)，二人共有2個小孩，分別為7歲和5歲。他和斯圖爾特的馬拉松地下戀情被攝影師描述為“似乎兩人都是意猶未盡”。

“克里斯汀這下全毀了，這是個錯誤，是完全的判斷失誤”，有消息向《人物》雜志稱。另一方面，也有對此持包容態(tài)度的消息，“她和魯伯特沒有關系。那只是極其短暫的瞬間，本不該發(fā)生。她不想傷害任何人。她是個好人，只是做了錯誤的選擇。”

斯圖爾特和帕丁森在不久前還一同亮相動漫展，二人還拿鏡頭前接吻的場景開玩笑的。

目前克里斯汀·斯圖爾特和山德斯的發(fā)言人對此都沒有表態(tài)。