"Before that it's just swimming endlessly and having no aim, no way to cope." The 38-year-old Sydney massage therapist sitting across the road from the Downing Centre District Court is HIV-positive, a diagnosis which entitles her to anonymity under NSW law. Ten years ago she was infected by a man - Chris Muronzi - who knew he was carrying the disease but maliciously decided to have unprotected sex with her on six separate occasions. Thanks to an appalling conspiracy of circumstances, including the negligence of doctors at an eastern suburbs medical clinic where she went to get tested, the woman then accidentally passed the disease to her new partner before she was diagnosed. She has just come from the courtroom where Muronzi, a 42-year-old Australian of Zimbabwean descent, appeared in a brief sentencing hearing on the charge of maliciously inflicting grevious bodily harm, a charge which carries a maximum seven-year jail sentence.

She has agreed to speak publicly about her experience for the first time in order to encourage people to take better care of their own wellbeing - both those who have the disease and those who do not. "I met him at an event where a friend of mine was modelling her jewellery," the woman says of her first encounter with Muronzi as a vulnerable 27-year-old. "I was a struggling make-up artist at the time. I was actually rejected [for a job] that night. I was told that I wasn't required or needed. I'd also recently finished a significant relationship. ... I wanted to have a really nice time with someone. Maybe I thought, here we go, we'll start a fresh with something different." Though Muronzi was not into using protection, their initial sexual encounters were safe ones. "It was a few months into it that I put my guard down," she says.

"I'd seen him more often and I'd seen him for a few months already." The woman had no idea that her lover had been diagnosed with HIV eight years before in 1995 and had been receiving treatment and advice from a Sydney doctor for all of that time. This included advice on managing his condition and his legal responsibility to disclose his HIV status to any sexual partners. He never gave even the vaguest hint to the woman that he had the disease, even when she rang and told him years later about her own diagnosis. It took a court-ordered blood test for the truth to come out.

The woman's discovery of her own condition was even more convoluted and painful. Her decision to get tested stemmed, simply enough, from a general discussion with her new partner about the attitude of Australian women towards safe sex. "It was a conversation bordering on an argument," she says. "He was commenting on Aussie women being a bit blasé about protected sex. He was generalising about it so we had an argument. I said, would you like me to have a test? Would it make you feel safer and better? So that's when I went ahead with the test." In March 2004 she went to the Bondi Junction Medical and Dental Centre.

The result was inconclusive but the recall letter for urgent retesting was sent to her old address, which she had given on visit to the medical centre in 1999. When the woman returned three weeks later, she saw a different doctor who called up her records on his computer. He did not read a note made by the centre's medical director, Dr Harry Johnson, that she needed a repeat blood test, and gave her the all-clear for HIV. About a week later she had unprotected sex with her new partner and infected him with the disease. It was not until June 3 of that year that Dr Johnson tracked her down and she was told of the need for another test, which confirmed the diagnosis of HIV.

"What the f---? those were the exact words that came into my mind," she recalls. "My jaw just dropped ... I couldn't deal with that reality. I was walking around in a daze. "I felt completely responsible at the time for him and for the impact it would have on him. It just devastated me, it was one of the worst days of my life. Inadvertently causing someone complete harm. Not knowing how to cope with that. I had never really had to think about that." Even harder, she recalls, was having to tell her partner. "I said, 'I don't have good news to tell you'.

"Just the simple possibility of him being negative was the hope as clinging on to. A few months passed before he go the courage to test himself. And it was positive." The man subsequently sued the Bondi Medical Centre and two of its doctors. The doctors admitted liability in 2009 and agreed to pay him $745,000 plus $197,500 in court costs. The company which owns the medical centre was ordered to pay him $300,000 in compensation two years later. The woman gave evidence during the court proceedings, devoting a huge amount of her time and energy to do what she could for him. But not long after her own health took a turn. She came down with Pneumocystis pneumonia, which forced her into hospital for the next six weeks. In hospital she suffered an allergic reaction to medications and near constant insomnia.

As well as being horrific, the experience was, in the woman's words "a dose of reality". She began taking anti-retroviral medications which she had previously avoided. She also decided to go to the police with her now overwhelming suspicion that Muronzi was responsible. "I realised that I had to go through the process ... I had to stop this happening to anyone else, first and foremost, but I also needed to do this for myself. I think going through the process was maybe my last attempt at gathering some information to help me let go." A blood test proved that Murzoni was responsible, and soon after he pleaded guilty, which entitles him to a 25 per cent discount on sentence when judge Penelope Hock hands down her decision in November.

The woman wants to see justice done, but she has a much stronger desire to move on and help others do the same. "If it doesn't feel right, don't go there," is her advice to others about sex, but also life more generally. And for those who do contract the disease: "Act soon for yourself. support yourself first because you're number one in this. Care for yourself." Muronzi will be sentenced on November 25.