Kelly Osbourne deeply regrets the "disrespectful" way she treated her mother during her days as a drug addict, insisting it's one of her "biggest resentments".
The singer-turned-reality TV star battled an addiction to painkillers for more than five years and she endured three stints in rehab before finally kicking her habit in 2009.
She has since managed to turn her life around and restore her image, but Osbourne admits she is ashamed of her rebellious behaviour and will always feel bad for putting her mum Sharon and rocker dad Ozzy through so much torment.
During an appearance on US talk show Anderson, which aired on Wednesday, she said, "I did a lot of really, really stupid things and it was because it was my way of crying for help...
"Not just drugs... Going out and staying out all night, and being disrespectful to my mother, which to me is one of my biggest resentments because I love my mum; my mum's my best friend. I hate the fact that I hurt her and my father. And my father, to a certain extent - now not so much, but at the time - blamed himself (for her addiction troubles) and that killed me."
And Osbourne has urged parents struggling to deal with drug-taking kids to adopt a "tough love" approach and send them off to seek treatment - because it's the only method that really works.
Asked what her advice to embattled parents would be, she replied, "Tough love if you're a parent...
"With my mother she didn't wanna believe it, she didn't wanna accept that I wasn't perfect because you love your children, but unfortunately nothing's perfect and as much as it hurts you you have to do the best thing, and you have to send your child to rehab. It is the only way to fix things, to teach you the skills and the coping mechanisms that you need to have a normal life and get your life back again. But having said that, it takes you to do it (too)."