The couple were said to have cut all communications following the revelation of Stewart's affair with Snow White and the Huntsman director Rupert Sanders last month. However, they are said to be on speaking terms again, albeit "barely".
According to In Touch Weekly, Pattinson recently began calling Stewart on the phone again.
"He's been drunk dialling Kristen. Rob had been avoiding her calls, but now they're talking... well, they're barely talking," an alleged source told the publication.
"There's a lot of dead silence on the phone, because there's not a lot to talk about. His friends are working hard to make sure that he doesn't go back to her."
Pattinson is said to be 'heartbroken and angry' over Stewart's fling with Sanders, as he had never previously been betrayed.
Photo gallery - Robert Pattinson and Kristen Stewart's relationship in pictures: