Kelly Osbourne's home workout

Apr 15, 2009, 4:00 GMT

Kelly Osbourne - She explained: "I have a terrible diet. Last night, I was eating Domino\'s pizza because I had nothing in my fridge and I couldn\'t go to the grocery store. I don\'t really work out either. I play on my Wii machine - I love the Wii Fit!" © Chris Hatcher / PR Photos

Kelly Osbourne is addicted to her Wii Fit.

The 24-year-old star - who recently completed a stint in an Oregon rehab clinic for an addiction to painkillers - is now obsessed with her computer fitness game.

She explained: "I have a terrible diet. Last night, I was eating Domino's pizza because I had nothing in my fridge and I couldn't go to the grocery store. I don't really work out either. I play on my Wii machine - I love the Wii Fit!"

But despite regularly working up a sweat with the electronic toy, the reality TV star insists finding true love with her fiance Luke Worrall, 19, has made the biggest difference to her life.

She said: "Being in love and being happy has got a lot to do with it. To be 24 years old and finally say 'I'm happy' is a really big deal for me.

"He makes me laugh, I trust him implicitly and he is my best friend. It's the best, when you're in love. It's everything."

Kelly - who plans to enjoy a long engagement before settling into married life - also revealed she is not a huge fan of weddings and believes they are not the only way to show your commitment.

She told Britain's New! magazine: "For me, marriage is just a certificate. As far as I'm concerned, Luke's the love of my life and that's all that matters."