Susan Boyle has opened up about her battles with depression saying that school bullying made her life an "absolute hell."

"I can be up and down like a yo-yo," she said. "I can be depressed."

The Scottish singing sensation Susan Boyle says her depression goes back to the bullying she suffered at school.

"I know I'm taking a big chance telling people this but you have to be honest. I used to be made a fool of at school," she said.

"It was psychological bullying and that leaves a scar and it also cultivates a lot of anger. "When people are a wee bit slow others pick at them. My life was made absolute hell."

Susan, whose new album, "I Dreamed A Dream" is topping the charts around the world said she still suffers from bouts of anger and mood swings.

Heartache: Susan Boyle opens up about her depression and buylling