The "Back to Black" hitmaker was rushed to the hospital in London in August 2007 to have her stomach pumped after ingesting a lethal cocktail of illegal substances.
Fielder-Civil, whose divorce from the singer was finalized earlier this month, was with his former partner at the time and admits they had taken "heroin and crack" before she suffered a fit and stopped breathing in their hotel room.
The 27-year-old reveals he was terrified that his lover would die and managed to save her life by clearing her airway and blowing air back into her lungs.
He says, "We were sitting on the bed talking. Her eyes went blank. She started having a fit on the bed. She slid down onto the floor before I could stop her. I was panicking; I didn't know how to help her. I was out of it on drugs as well. I knew it was important to stop her choking so I turned her over onto her side, putting her in the recovery position. Then I pulled her tongue out of her mouth so she wouldn't bite it. She had an awful look on her face, just pale and frightened.
"I thought she was dying in my arms. She kept on fitting, but then suddenly she passed out and stopped breathing. I felt sure I was watching her die right in front of me. Somehow I managed to open her mouth and breathe down her throat. Then she spluttered and I saw her chest rise. I was still sobbing and panicking but I just felt this huge relief she was alive."
Fielder-Civil admits the night his wife was taken to the hospital was not the first time she had suffered a seizure -- the Grammy Award winner began experiencing "mini-fits" during their drug-taking, but she insisted on carrying on.
He adds, "She had everything going for her. But she ended up behaving badly just to shock. I'd warned her to stop but she always wanted to keep on taking drugs. All that talent and personality -- and she hid them behind drink and drugs.
"I think having seizures and just carrying on -- that is pretty shocking, pretty hardcore behavior. It's not something I would be able to do."
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