Britney Spears is upset by Sam Lutfi's recent court claims.

The X Factor judge's former manager is suing her parents for defamation and during the trial he has claimed Britney was addicted to drugs when he managed her but the singer, who has gotten her life back together following a much-publicised breakdown in 2008, is upset by his revalations.

"Over the past four years you'd hear Britney's name and the first thing you'd think of was shaved head, psych hold, umbrella. But she got her life straightened out and now you think music, glamour, that big smile. The court case couldn't have come at a worse time," a source said.

Britney's friends are also worried about the star having to relive her past troubles. "She's long battled mental health issues so to be reminded of this time in her life, when she almost died, is devastating. No one should have to relive what she went through," the insider added.