Troubled singer Britney Spears says her new, reformed life feels worse than prison.

Having suffered a very public breakdown last year — which saw her shave her head, lose custody of her children and end up in rehab — the singer admits her new lifestyle is a passionless prison.

Spears reveals in her new documentary, 'Britney: For The Record': "There's no excitement, there's no passion. I have really good days and then I have bad days.

"Even when you go to jail you know there's a time when you’re gonna get out. But in this situation it's never ending. It's just like 'Groundhog Day' every day.

"I think it's too in control. If I wasn't under the restraints I'm under, I'd feel so liberated. When I tell them the way I feel, it's like they hear but they're really not listening.

"If you do something wrong in your work, you can move on, but I'm having to pay for a long time.

"I never wanted to be one of those prisoner people. I always wanted to feel free."