The devastating story that led to Susan being found passed out drunk in her car at midday.

It was around 12:30pm in November of last year when police found 42-year-old mum Susan Lund passed out drunk in her car.

She was parked in a bus stop in Sydney’s North Shore, and was nine times over the legal blood alcohol limit, with a blood alcohol concentration of 0.445 – one of the highest recorded in NSW.

But this isn’t the entire story.

In a preview for Sunday night’s episode of 60 Minutes, Susan says she’s not an alcoholic – despite having consumed nearly two casks of wine in two and a half hours.

The Willoughby resident said that on the day of her arrest, her husband of 24 years had announced he was leaving her. After dropping her children at school, she pulled over on a random suburban street, not realising she was in a bus zone.

“(I was) just sitting there thinking, ‘What’s happened to my life? Where did it go wrong?’” she tells 60 Minutes.

“And then I remembered that I had wine in the back, so I just pulled it into the front and just took the first sip, and then from there I think it just went downhill.”

Watch the preview for Sunday's 60 Minutes below. Post continues after video.

Despite this, Susan will be allowed to keep her licence.

Following her hearing at Hornsby Local Court on April 12, her charge was withdrawn as police were unable to prove that she had driven in the two hours prior to her breath test, and the 42 year old mum said she was sober when she parked the car and was there until she was caught by police.

"It’s not illegal to sit in your car and drink,” she said.

Cameron Daddo: "I understood that I needed assistance. I needed to understand what my behaviour was all about..." Cameron Daddo opens up to Mia Freedman about his battle with addiction, on No Filter. Post continues after audio.

According to ground-breaking research conducted by Western Sydney University in 2015, more than 624,000 Australian women aged 35 to 59 years old engage in high-risk drinking.

Speaking to the ABC, lead researcher of the study Dr Janice Withnall said that this was due to the lack of a national alcohol strategy and greater awareness which means at-risk women have "limited coping abilities" and as a result tend to "take solace in alcohol."

Regardless of whether Susan's encounter with the police was an isolated incident, she acknowledges, "working full time, doing the kids, never having a day off is hard".

Susan's story will air on 60 Minutes tonight at 8:40pm, on Channel Nine.