Gwen Stefani is thrilled with the limited leisure time her busy schedule affords her - because she feels "worthless" when she's not working.

The RICH GIRL singer, married to British rocker Gavin Rossdale, admits she doesn't like too much relaxation time, because she constantly needs to feel like she's achieved something.

She says, "I'm always sad when I take time off. I'm addicted to the rewards I feel when I accomplish things. If I don't do things, then I start feeling self-hate. I feel worthless."