Relations between Britney Spears and her mom are reportedly becoming increasingly strained - so much so that the popstar refused to visit her in hospital on Mother's Day. "Britney has cut off all communication with her mom," a source told the National Enquirer. "She's gone from calling Lynne ten times a day to flat-out refusing to speak to her." Lynne Spears was hospitalized when a bad flu developed into pneumonia. Other tabs are also reporting the story. "Britney says her mom betrayed her and she refuses to get over it," says the source. "When she was told to give her mom a call, Britney said, 'I'm busy, I have my own kids now.'"