Tumours are growing like cauliflower in her lungs, and they will eventually solidify and crush her organs.
After 10 years of chemotherapy and surgery, doctors have told Mrs Williams that she should focus on her quality of life, not quantity.
The 58-year old, who divides her time between Greens Beach and central Victoria, has been to at least 60 funerals for people who have died from asbestos-related diseases.
She can't explain why her own case of mesothelioma hasn't killed her yet. But she says she will raise awareness for asbestos and its dangers until her last breath.
Mrs Williams's advocacy role with the Bernie Banton Foundation has taken her across the globe, her campaign giving a voice to thousands of victims and families.
In March, she was a guest speaker at the international Asbestos Disease Awareness Organisation forum, travelling to the US, despite finding it difficult to walk up a set of stairs.
Mrs Williams is also lobbying the federal government to remove asbestos from houses and public buildings.
She said her goal was to see the removal, storage and transport of the hazardous material heavily subsidised for homeowners and renovators.
``Medically, we are well aware of what asbestos can do, but the general public is still so blaise,'' she said. ``Things like home renovations - no one wants pay a big fee for someone to come and inspect and remove asbestos.
``People say it's all hype and hysteria - but the reality is, you only need minimal exposure to be affected.''
Mrs Williams said her first contact with asbestos was as a small child in the 1950s, when her father built her a cubbyhouse from leftover fibro sheeting.
In the 1970s, she unknowingly worked at a Melbourne office that was riddled with the toxic material.
For three years she breathed in invisible asbestos particles dislodged from the suspended ceilings and insulator cables.
``Back then no one gave asbestos a second thought,'' she said. ``We just didn't know. But already it has been too late for thousands and thousands of people, who were all exposed without being aware.''
High-profile court cases throughout the 1980s set a precedent for civil damages to be awarded to sufferers of asbestos-related diseases by their former employers.
Mrs Williams's father succumbed to mesothelioma in 1985, aged 54, after years in the plastering trade.
``He went down fast, and it was a very painful death,'' she said.
Throughout the 1990s, Mrs Williams herself suffered unexplained fatigue and headaches, as well as unusual swelling in the abdominal area.
But it wasn't until 2003 when advanced scans revealed tumours in her stomach and diaphragm.
``Even then, mesothelioma was relatively unknown - my doctor could not even pronounce it,'' she said. Mrs Williams was told she had two to three months to live if her treatment was not successful.
A marathon 18 sessions of chemotherapy put the disease temporarily at bay, but in 2009, it returned to her right lung.
She endured three more surgeries and 12 more sessions of chemotherapy.
In September last year she learned that her left lung and diaphragm were affected.
``I've been told there is nothing more that can be done - no doctor will touch me,'' she said. ``I'm not sure how much time I've got left.''
This week, Mrs Williams will travel to Melbourne to explore a radical radiotherapy option - one that would be painful and cause irreparable damage to her organs.
But she said she was determined to keep fighting.
``There are so many people who have not been as lucky as I am.
``There is still a lot to do. I want to be a voice for people.''