Jealousy is wrecking the headline-making romance of mopey “Twilight” stars ROBERT  PATTINSON and KRISTEN STEWART, say sources.

“Rob is stewing over her post-‘Twilight’ breakout success, while he’s struggling to find his footing,” revealed an insider. “His latest movies – ‘Water for Elephants, ‘Bel Ami’ and ‘Remember Me’ – have all been critical and commercial duds.

“Meanwhile, Kristen’s latest, ‘Snow White & the Huntsman,’ is doing big business, and she’s being flooded with work offers.”

In a huge boost to the red-hot star’s career, Kristen is rumored to be a frontrunner for the lead female role in the movie adaptation of the steamy best-seller “Fifty Shades of Grey.”

“But Rob is dead-set against Kristen taking such a sexually charged role,” disclosed the insider. “Kristen feels betrayed – she doesn’t think Rob’s a supportive boyfriend.”

To make matters worse, sources say, Rob is demanding his girlfriend cut back on work to spend more time nurturing their relationship – and he’s tired of distance separating them.

“But Kristen thinks Rob is behaving like a sulking baby,” revealed the insider, and their romance of nearly three years has been pushed to the brink.

In late May, Kristen walked the red carpet alone at the premiere of “On the Road.”

“Rob refused to be photographed with her,” said the insider. “He hates the limelight.”

That same month Kristen was nowhere in sight for Rob’s 26th birthday celebration in London, even though she was in town.

“Their career rivalry is driving a serious wedge between them,” said the insider. “They’re headed in opposite directions.”