Anna Nicole Smith insisted to the father of her daughter that she was not a drug addict but "in pain", he has told a court.
Larry Birkhead testified he saw her taking numerous prescription drugs but that she told him she was not an addict.
Birkhead said he was so concerned about her excessive use of medications that he once hid her methadone only to be scolded by Howard K Stern, who said she couldn't live without it.
"She would say, 'I'm in pain. I'm not a drug addict,'" he recalled.
When he suggested she was taking too many drugs, she replied, "I have a high tolerance because I'm in pain," he said.
Birkhead, a photographer and reporter, sat on the witness stand facing two people who had fought him for custody of Anna Nicole's child: the late model's lawyer-boyfriend, Stern, who is on trial in an alleged drug conspiracy, and the model's mother, Virgie Arthur, who was in the audience.
Birkhead told jurors how he and Anna met in 2004 when he photgoraphed her and other celebrities at a Kentucky Derby party. He said he eventually moved into her Los Angeles home where a number of people were staying, including Stern, her personal assistant, and her son, Daniel.
Her neighbour was psychiatrist Dr Khristine Eroshevich, he said, and sometimes Stern would call her when Anna Nicole wasn't feeling well.
Stern, Eroshevich and Dr Sandeep Kapoor have pleaded not guilty to conspiring to unlawfully provide excessive drugs to the model, prescribing to an addict and obtaining false prescriptions involving the use of fake names. They are not charged with causing her overdose death in 2007.