2013 really hasn't been the best year for Nigella Lawson, and she has now been branded a 'habitual criminal' who created a 'culture of secrecy' in her marriage by hiding her alleged drug use.

The 53-year-old TV chef was accused in court yesterday of allowing former assistants Francesca and Elisabetta Grillo to spend around £685,000 on a credit card belonging to her and ex-husband Charles Saatchi in an attempt to stop them revealing her illicit habit - which reportedly included snorting cocaine on a daily basis, smoking cannabis and abusing prescription medicine - to her spouse.

Art dealer Charles says he discovered Nigella's secret shortly before they ended their marriage earlier this year and branded her 'Higella' in a rage-fuelled email in which he claimed she was so 'off her head' on drugs she couldn't remember giving the Italian sisters permission to use the credit card.

Anthony Metzer QC, who is defending Elisabetta in an ongoing fraud case, insisted his client is simply a 'pawn' in the marital woes between Charles and Nigella. He told Isleworth Crown Court in west London on Tuesday: 'Mr. Saatchi is saying Miss Lawson is a criminal because she has been partaking in Class A drugs habitually at home, and Class B.

'The defendants' case is that Nigella Lawson lied to her husband about her drug use and expenditure incurred by the defendants -- both expressly and implied. She was fearful of Mr. Saatchi's reaction if he knew about the extent of the expenditure and drug use. There was a culture of secrecy within Nigella Lawson's marriage. She was aware that the defendants knew she was a habitual drug user and allowed this expenditure.'

Charles is set to be quizzed in court today about his discovery of his former wife's drug use, but said in a statement that he learned of her habit in June 2013 - around the time he was infamously pictured gripping the TV star by the throat at a London restaurant.

Nigella, meanwhile, is being tipped to appear in court tomorrow to address the claims.