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Kelly Osbourne has made a name for herself as an outspoken co-host of the fashion critique show "Fashion Police," and she's engaged to be married - but things weren't always so wonderful for her.

The daughter of Black Sabbath rocker Ozzy Osbourne and "The Talk" co-host Sharon Osbourne has had her share of personal problems, including a struggle with drugs.

In a new interview with Cosmopolitan U.K., Osbourne, 28, discussed how supportive her mother was during her various stints in rehab and revealed the lengths Sharon Osborne went to in order to get her off drugs.

"My mum even had me put in a padded cell once to scare me but, like a brat, I just sat it out until she said, 'Well, that's not going to work', but what I've learnt is that no amount of therapy or medication is going to work unless you want it to," Osbourne said.

Osbourne spoke to ABC News' Bianna Golodryga two months about what finally made her come clean and turn her life around.

"I was sick and tired of not liking myself for no reason and believing what everyone said about me," she told Golodryga. "I thought, 'Well, if they say that I'm a drug addict…why don't I just be that then?"

Osbourne told the magazine that when her mother was diagnosed with cancer in 2002, she had to choose between a coveted movie role or helping her mother - whom she has called her best friend - through her illness.

"I was faced with the choice of a career or spending what could have been the last days of my mother's life with her. … I became my mum's nurse 24/7," she said.

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Sharon Osbourne also underwent a double mastectomy after her cancer scare, an action her daughter described as "brave."

"It's a huge, huge decision and you have to be brave to go through that," Osbourne told ABC News' Golodryga.

"She's bloody annoying," Osbourne said, laughing, of her mom. "But she is my best friend."

Osbourne recently got engaged to longtime boyfriend Matthew Mosshart, and she told Cosmopolitan that she wanted to start a family one day.

She said she wants a boy and a girl, adding: "When I do … I will not have a baby call me mom."

She also talked in the interview about her struggles with her weight.

"I can't lie; it's been hard having people say, 'You're fat,' and, 'You're a beached whale,' but I've been judged since I popped out, and I've never known anything else," she said. "What's been great is overcoming that and understanding that these people are just idiots who hurt your feelings because they want a reaction. I'm proud of proving them wrong."

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Jacqui Meddings, the magazine's entertainment editor, called Osbourne "a total inspiration to young women."

"It's so raw and honest for her to speak in that way and you really feel for her and Sharon's battle as well…for a mother to see her daughter so desperate," Meddings said.