He said that the troubled singer became unconscious and stopped breathing at their hotel room in London in August 2007 after which she was taken to her hospital to have her stomach pumped.
"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," Contactmusic quoted him as saying.
He described: " 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."
Blake added that he asked her to stop consuming drugs once she started having "mini fits" but she would not listen.
He said: "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 behaviour. It's not something I would be able to do."