The then 42-year-old was lying in a hospital bed after having lost sensation in the left side of her body.
She thought it a really bad inner-ear infection or that something was wrong with her neck.
But what began as general fatigue and vertigo actually turned out to be symptoms of MS.
“The doctors were saying it could be the result of a stroke or MS,” Ms Kingsford Smith said.
“The minute I heard MS, I said: ‘Not me, I don’t want it.’ I didn’t know what MS was but I knew I didn’t want it.”
Multiple Sclerosis sees the immune system eat away at the nerve’s protective covering and affects three times as many women as men.
“Doctors think I probably had the disease anywhere from two to five years before being diagnosed,” Ms Kingsford Smith told news.com.au
“I was really fatigued, had been suffering vertigo, and found myself clinging to walls and having trouble with spatial awareness for a while.
“I assumed it was because I was a busy career and party girl, so thought it was normal.”
And while the news was devastating, the 47-year-old is getting on with life.
But most importantly she wants to break down the stigma surrounding the disease and dispel the myths surrounding it.
“You don’t die from MS, you die with it,” she said.
“It’s not an automatic sentence to a wheelchair either.”
With World MS Day on Wednesday, Ms Kingsford Smith said it was important people were more aware of the symptoms and also called for more understanding of what people with the disease go through.
“I’ve been kicked out of restaurants because the manager has assumed because I can’t walk in a straight line or that I’m slurring my words that I’m drunk,” she said.
However she said people are understanding once she explains what’s really wrong.
The theme for this year’s World MS Day is Life with MS which looks specifically at the quality of life for people with the disease and those close to them.
MS Research Australia has also released some research into the myths surrounding the disease to coincide with the Kiss Goodbye to MS campaign which has run throughout the month of May.
The findings showed half of the population don’t know what MS is and are unable to identify early symptoms, while one in five believe everyone with the disease will end up in a wheelchair.
Around 23,000 Australians have the disease.
While Ms Kingsford Smith had to sell her digital marketing agency due to the disease, she is attempting to turn it into a positive experience.
The author and writer is currently publishing her third book in the MS Taking Control series and said the disease made her reassess her life, forcing her to declutter and de-stress.
A Kiss Goodbye to MS ambassador, Ms Kingsford Smith is promoting the Wall of Kisses at the Teneriffe Festival in Brisbane on July 1.
But she admits she has her bad days where she can’t get out of bed despite having hours of sleep and having a shower is a huge effort. Crowds and loud noises are also too much.
Other days she feels fine, which can be hard for people to understand.
While there is no cure for MS, there are treatments and therapies available which can slow it down, but people often have to find one which suits them.
Ms Kingsford Smith said she didn’t want people to feel sorry for her and that it was important to focus on the positives, including having a supportive family and friendship network.
“My life hasn’t stopped, it has just changed,” she said.
“This disease has forced me to make big changes in my life to protect my health. I pulled my life apart and put it back together again and it’s given me a new edge.
“Without your health you have nothing.”
Ms Kingsford Smith said also remained hopeful with further research that a cure would occur in her lifetime.
“I think of the advances that have taken place in the past few years already, so who knows what will happen in the next five years,” she said.