Robert Pattinson and Kristen Stewart on a Break?

Robert Pattinson and Kristen Stewart

Rob's absence on the Breaking Dawn set has put the Twilight star's relationship in jeopardy.

Twilight costars and off-screen couple Robert Pattinson and Kristen Stewart may be calling it quits after years of avoiding the media's fascination of whether they were or weren't a couple. Even in Robert's latest interview with Vanity Fair, he carefully avoided any talk about being in a relationship with Kristen. Robert Pattinson Holds A Croc, Talks Kristen Stewart Rumors  

But it wasn't hard to figure out the two were together based on their fond comments for one another in interviews and public displays of affection (the two were finally caught kissing off-screen in August 2010). And naturally, Oprah got the couple to admit what no one else could, that they were together and crazy about each other. Robsten Confirms To Oprah That They're Dating

Now, though, rumor has it that they have been growing apart since February and are "on a break." Just this past weekend, Robert attended the Country Music Awards...alone. And Rob's been missing on the Breaking Dawn set lately to film Water for Elephants.

"They both have hectic work schedules, Rob in particular at the moment, and their phone calls were getting fewer and further between. They started to only see each other on set and began to drift apart until a general apathy developed," a source said via . "The excuses why they couldn’t meet up basically got weaker and weaker, and Rob figured they should officially cool things off and have some time to figure out what they each want."

This isn't the media shy couple's first split. Goodbye To Robert Pattinson And Kristen Stewart? They called it quits in October 2009, and again in 2010, but always seemed to come back to one another. While we're not convinced the two are permanently over (word is Kristen is pushing for them to makeup), we wonder what will happen to the pair once the Twilight movies wrap for good?