"Then for two years I barely left the couch," she said.
"I shut the front door and I basically wasn't letting anyone in or going out."
Now, she's back on track and rebuilding her love for life by setting off to ride the length of New Zealand with Indy - her border collie, Burmese mountain dog cross.
"I was what they called a high-functioning person... and it all stopped," she said.
Becoming more "self-accepting" was an important part of recovery for Ms McNaughton.
"It's been a year of recovery and a long time spent planning this."
She hoped her story would help others, she said.
"I think in terms of a message to help other people, its really important to find people that they can talk to."
Part of that recovery was a cycle from Twizel to Oamaru with Indy alongside her, and it went well.
She came up with the idea to get back into her endurance sport, travel New Zealand, and raise money for regional charities.
The journey from Cape Reinga to Bluff will take her four months.
"It's perfect for me. It's everything I did [before the breakdown], and it's helping people. I would never do it without Indy, and she is just great for starting the conversation with people," Ms McNaughton said.
Indy rides in a carriage attached to her owner's mountain bike, which she seems very at home in.
The carriage is padded, has a sun shade and is big enough for Indy to sit up inside, or lie down inside.
On difficult roads, Indy can run along side Ms McNaughton, and there is a support vehicle manned by Brazilian tourist Leonardo Noronha, who carries all the camping gear for the trip.
Ms McNaughton is hoping people will follow her journey and even participate with her.
"I want families to come out and ride with me. I'm not going very fast, I'd encourage people to get and about with me," she said.
All donations will be split between 13 regional charities for the different regions she will be travelling through that have a personal connection to her.
The charities are:
Auckland Regional Helicopter Trust, Sport Northland, Cambridge Riding for the Disabled, Manawatu-Wanganui Disaster Relief Trust Fund Charity, Cranford Hospice, MenzShed Waimea, Performing Arts Trust Wellington, Tasman Environmental Trust, Marlborough Falcon Trust, Coastguard West Coast, SPCA Canterbury, Otago Medical Research Foundation, Number 10 Southland
If you want to support Leisa on her journey visit givealittle or www.leisa.kiwi to follow her as she makes her way south.
Where to get help:
• Lifeline: 0800 543 354 (available 24/7)
• Youth services: (06) 3555 906
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• The Word
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• CASPER Suicide Prevention