'It started as an ordinary work day. By the end of it, I couldn't remember where I lived.'

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As told to Rebel Wylie.

Before 2016, I was living at full speed.

I was running a successful law company, and I was flying all over the world speaking at tech events — often standing on stage in front of thousands.

Outside of work, I was training for marathons and triathlons. I was strong, confident and constantly moving.

If I wasn't working seven days a week, I was running or lifting weights. Looking back, I see someone who was almost blindingly fearless.

Before the accident, finishing the Great Wall of China marathon. Image: Supplied.

Then, on 18 January 2016, a fire extinguisher exploded in my face — and everything changed.

It was 18 January 2016, and I'd organised fire safety training for the office.

Typical, busy me. I was always leaving things on the stove and coming back to a kitchen full of smoke. I told my team it was just common sense — we all needed to be trained.

But that day, something felt off. My skin was crawling, my nerves were shot. The bang of the extinguishers being tested made me want to jump out of my skin.

Everyone else had their go. Now it was down to me.

I picked up the big red canister, hose in one hand, trigger in the other. I braced myself, turned my head away and squeezed.

Nothing. I tried again. Still nothing. So I tried once more.

The nut under the handle gave way and the canister blew. The pressure forced the hose into my face, again and again.

My C6 vertebrae fractured. Ligaments in my jaw tore. My teeth chipped. My face was cut and bruised.

I staggered to the car park. My keys opened a car, so I guessed it must be mine.

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But once I was in, I couldn't figure out how to start it. I'd forgotten it had push-button ignition.

When I finally got it going, I drove to my old apartment — the one I'd moved out of six months earlier. I pulled into the carpark, furious that someone else was in "my" spot.

Mid-drive, my mum called and reminded me that I didn't live there anymore.

That night, I took a sleeping tablet and passed out for 14 hours. When I woke the next day, my whole body was screaming in pain.

The emergency sent me away. My GP said it was "just concussion." But I knew it wasn't.

The new me.

From that day on, I wasn't Katie Richards, the marathon-running CEO anymore. I was someone who couldn't handle light or sound, who draped a chiffon shawl over her laptop screen just to get through emails.

Someone who had the same conversations on repeat because she couldn't remember what she'd said five minutes earlier.

Noise triggered migraines. Simple conversations overwhelmed me.

I couldn't remember what I liked to eat. Not that it mattered because I also couldn't taste or smell food for the longest time, which made it hard to remember what I did like.

The piano I'd played since I was four? Gone.

I couldn't recall basic points of Australian law, despite spending over $100,000 on my education.

Once, a woman in my networking group asked about the accident. In the middle of speaking to her, my brain just... stopped.

She stared at me in horror as I glazed over. I watched it happen, like I was outside my body, trapped behind a screen. That was the last time I went out for months.

Everyone has that one thing they value most about themselves. For me, it was my intelligence.

And my brain was failing me.

The darkest days.

Money ran out quickly. There were weeks when I couldn't even afford parking for client meetings. I kept the business barely alive by working in one-hour bursts — pushing through the pain, directing my team, collapsing into sleep, then trying again later.

But there were nights where I wished I wouldn't wake up. The only thing that stopped me doing anything to end the pain was knowing I couldn't put my mum through that.

And the people I'd poured my time and energy into? Most of them vanished. Only a handful stayed.

One friend in particular kept showing up, dragging me out of the house, reminding me I was still here. That loyalty saved me.

Looking back now, I can see that part of the reason people disappeared was because I wasn't honest about how bad things really were. I kept saying I was fine, when the truth was, I was drowning.

I thought being strong meant putting on a brave face. But all it really did was push people away. I had to learn that vulnerability isn't a weakness — it's what allows people to actually show up for you.

Letting others see the reality, even when it was messy, became one of the hardest — and most important — lessons of my life.

Rebuilding, file by file.

An occupational therapist finally gave me an explanation that made sense. She told me my memories were all still there, but it was like someone had tipped out the filing cabinet.

Everything was still there. Just in a pile. To put it back together, I had to start small.

I used to be fluent in Japanese. She told me to relearn the basics. I tried to count to ten, but only made it to six before I broke down crying.

That night, I woke up with my head flooded with Japanese phrases.

She was right. One file unlocked the rest.

That's how I rebuilt. Tiny pieces at a time.

I retrained, becoming a lawyer in the UK, which helped trigger the memories of Australian law that I had lost.

Slowly, my skills came back.

I trained my body too. I couldn't run marathons anymore, but I could lift weights to keep my neck strong.

If I stopped, the migraines returned. Exercise gave me just enough endorphins to want to keep going.

I also faced PTSD.

Once, I sat in on another fire safety training session. I told the trainer I wouldn't touch the equipment and explained what had happened to me.

Halfway through, he accidentally turned the hose towards me. My body went into full panic, cold sweat, breathless, shaking.

By the time HR came to check on me, I was on the floor, crying and gasping for air.

A second chance.

By the time COVID hit, one of the platforms I'd built took off.

We started winning awards again. Helping others reminded me I was still valuable.

Post-accident winning Tony Robbins Business Master Team Challenge. Image: Supplied.

Today, I run multiple thriving businesses. I've learnt to set realistic goals. I've learnt to rest.

I've learnt that even protectors and carers need to let people care for them, too.

I've learnt that life is unpredictable.

I live now knowing that everything — even the darkest setbacks — can be survived.

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Feature image: Supplied.