Sharon Osbourne has revealed that she had a "complete, utter breakdown" last year.
The 63-year-old was missing from her TV show, The Talk, for six weeks last May.
At the time, her rep told E! Online that Osbourne was suffering from "extreme exhaustion", but the TV personality revealed the truth yesterday.
"I had a complete, utter breakdown," Osbourne admitted on The Talk.
"I woke up in Cedars-Sinai Hospital and, for probably three days, I knew nothing. I couldn't think, I couldn't talk. I could do nothing. My brain just shut down on me."
Osbourne blamed the breakdown on "doing too much of everything, thinking that I'm Superwoman".
"I just couldn't cope with anything and my family put me into a facility. And in this facility they diagnose you, and you do a lot of group therapy.
"The group therapy was the best, because there were other people suffering from the same thing. I didn't want to talk, didn't want to eat, didn't want to speak to anyone."
The mother of three now has a "good grip" on her condition and urged anyone else who might be suffering from depression to seek help.
"It's nothing to be ashamed about," Osbourne said.
"If you had a bad leg, you tell everybody you had a bad leg. I just have a bad head."
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Where to get help:
• In an emergency: call 111
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youthline: 0800 376 633, or text 234 (available 24/7) or email@example.com or live chat (between 7pm and 11pm)
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155 (weekdays 11am to 5pm)