Ozzy Osbourne became so paranoid on drink and drugs he thought Sharon was plotting to kill him.
She reportedly walked out on the Black Sabbath rocker after an 18-month battle to get him to overcome his addictions, finally reaching breaking point when he didn't sleep for six days.
A friend revealed to the Daily Star Sunday newspaper: 'He kept accusing Sharon of plotting to kill him. It was heartbreaking for her.
'He was screaming and sobbing, 'They are trying to kill me. Sharon's trying to kill me'. It was horrendous.
'He was living in an imaginary world for most of the time and seeing a lot of things that weren't even there.'
It is said the 64-year-old star doesn't remember all of these incidents, which included going for days without washing.
The source added: 'Ozzy knows he's put Sharon through hell but the truth is he can't even remember half of what he did.
'Recently he was so out of it he survived for nearly a week without sleep and just made Sharon's life pure hell. He was running around in the same clothes all the time, not washing.'
Ozzy's booze binges would sometimes start before breakfast and although he is hoping to 'win her back', the former 'X Factor' judge isn't as keen.
The insider said: 'Sharon has been through it so many times before that she's asking herself, at 60, does she really want to spend the rest of her life like this?
'Ozzy keeps calling her around the clock but she's ignoring a lot of it ... [He] seems to think he can win her back, but Sharon isn't so sure as she's been living in a private hell.'