Justin Timberlake is giving Britney Spears a dose of tough love – in the hope that she might clean up her act. Since her break-up with Kevin Federline, the troubled songstress has allegedly bombarded her other ex, Justin, with phone calls. “She would sometimes call him 10 or 12 times in a row before he’d finally give in and take her call,” a friend of Britney’s reveals. The pop stars met while performing on the oickey oouse Club show and dated in 1999. The `Sexy Back’ singer has been deeply upset watching Britney’s life unravel, according to insiders. “Loyalty means a lot to him, and when Brit started calling him last year, he tried to be there for her as much as he could. I know that it is crushing him to see her this way. They grew up together. They were each other’s first loves. Their mothers remain good friends.” But in a desperate bid to help Britney, Justin has reportedly changed his phone number and warned friends not to help Britney contact him. “He felt it was a mistake to let her use him as a crutch. He had to go the tough-love route – just as her own mom did – and say if you want me in your life, you have to clean up first.” [8 March 2007]