Flashback: Inside Robert Pattinson's Tortured Romance With Kristen Stewart

USMagazine, Wednesday, July 25, 2012, 3:30pm (PDT)

The warning signs were all there.

Back in 2010, sources close to Robert Pattinson predicted it was just a matter of time until Kristen Stewart stomped all over their pal's heart.

Multiple insiders spoke to Us Weekly at that time about the problematic dynamic between the couple, who began quietly dating in 2009 after meeting on the set of the first Twilight installment.

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Even then, Pattinson was "telling his closest circle" that he wanted "to ask Kristen to marry him. He's never felt this way about anyone before," one insider said of the "head over heels" actor. Stewart, for her part, wasn't quite so confident in her feelings for Rob.

"He thinks she's The One. But she just doesn't love him as much," one Pattinson source explained. And though Stewart was "totally into him -- for right now," as the source put it, in the end, their relationship wasn't her "end all be all" the way it was -- and presumably still is -- for the British-born star.

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Pattinson -- whom pals describe as "more emotional and sensitive" than Stewart -- picked up on his girlfriend's distance, and feared that "his feelings are more serious for her than hers are for him."

After one year together, Pattinson hoped to solidify his bond with Stewart by going public with their romance -- but Stewart was much more reluctant to take that step together.

"It's sad for him because he's ready to admit his love to the world, and she's not," the insider said. Indeed, it wasn't until October 2011 that Stewart finally confirmed their relationship -- by accident. Speaking to a GQ writer, she commented that, while in the U.K. for Snow White and the Huntsman shooting, she hoped to explore the country more "because my boyfriend is English."

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Thanks to that very film, Pattinson's worst fears were ultimately realized. In late July, Us Weekly obtained photos of Stewart engaged in a steamy, extended makeout session in L.A. with Snow White's director Rupert Sanders, a married father of two nineteen years her senior.

In a moment of uncharacteristic candor, the actress released an emotional statement Wednesday, apologizing for her actions and professing her love for Pattinson.

"I'm deeply sorry for the hurt and embarrassment I've cause to those close to me and everyone this has affected," Stewart said. "This momentary indiscretion has jeopardized the most important thing my life, the person I love and respect the most, Rob. I love him, I love him, I'm so sorry."

This article originally appeared on Usmagazine.com: Flashback: Inside Robert Pattinson's Tortured Romance With Kristen Stewart