Robert Pattinson's departure from a Hollywood bar with Disturbia actress Sarah Roemer, has sparked rumors of a possible breakup with his girlfriend and co-star, Kristen Stewart.

Pattinson and Stewart have been one of Hollywood's most talked about couples since rumors of a relationship between the two started in 2008 when they began working together for the Twilight series.  The couple is currently ranked number one in Pop Sugar's Favorite celebrity PDA moment of 2011 poll.

On Sunday night, Pattinson was spotted leaving a bar and getting into a car with Roemer in Los Feliz.. Pattinson looked scruffy with his overgrown beard, checkered shirt and a cap. That he and Roemer were photographed so closely inside the car has put doubt into his relationship with Stewart who is currently in London filming Snow White and the Huntsman.

Rob was literally fending off advances from girls, left and right. Every female in the bar wanted to get close to him and for the most part, he politely ignored them but one girl caught his eye and she left with him, a source told Ace Showbiz.

It was only last week that Pattinson was in London with Stewart, reportedly having several date nights and wer still a happy couple.

Stewart confessed that she was dating Pattinson earlier this year, but since then the couple has kept extremely private about their relationship. Stewart told GQ magazine that she would never speak openly about her relationship.

'I don't worry about it at all. It's just one of those things. I'm selfish. I'm like, That's mine! And I like to keep whatever is mine remaining that way. 'It's a funny little game to play and it's a slippery slope. I always say to myself I'm never going to give anything away because there's never any point or benefit for me.' 

Contrary to rumors, Gather.com claims that Pattinson's relationship with Stewart has been growing. In a recent interview with Hollywood Life he disclosed that his favorite part of filming the Twilight series was kissing his girlfriend.