TRIGGER WARNING: This story deals with suicide and related issues and may be upsetting for some people.

When Carissa Avison went missing in Auckland in 2017, rumours swirled and speculation was rife about what had happened to the 21-year-old.

The usually reliable Auckland Transport employee was reported missing after she failed to show up at work.

Apart from a CCTV image, there was no sign of her until weeks later when a couple walking their dog at Muriwai chanced upon her body.

Now, a coroner has pieced together what happened to Avison.

Police - who ruled out anything sinister early on - searched for her using dogs and the Eagle helicopter. After eight days they called off the search.

Her body was found by chance, hidden from most views and on a remote track, on February 15.

After an inquiry into Avison's death Coroner Mary-Anne Borrowdale released her findings today.

She ruled Avison's death was a suicide.

In the 24 hours before she died Avison took an online depression quiz, wrote a final letter and researched how to wipe her social media.

Carissa Avison was a regular social media user. Photo / Facebook

Avison's inquest was held on papers, meaning Coroner Borrowdale did not deem a public hearing in a courtroom necessary. But she did feel there was public interest in what happened to Avison.

Her brother told the Herald the report was "very hard to read" but answered questions he had about her death.

Avison's childhood and teenage years, Coroner Borrowdale said, held "very limited stability".

Her parents divorced when she was young.

"By the time of her death, there was considerable discord and fragmentation within Carissa's wider family group," said the Coroner.

"It is possible that Carissa's employment was the most stable anchor in her life."

Avison worked as a customer feedback coordinator for Auckland Transport.

By all accounts - from colleagues to managers - she was "well liked" and regarded as "a valued employee".

Avison had a great attendance record and was always reliable.

She didn't have a wide circle of friends and didn't socialise much - also living largely independently of her flatmates - but had a "frequent and active" presence on social media.

"Carissa was an active young woman," said Coroner Borrowdale.

"She enjoyed the outdoors and especially pursuits like four-wheel driving.

A Coroner has released a report into the 2017 death of Carissa Avison whose disappearance sparked a massive search across Auckland. Photo / Supplied

"Her grandparents had lived at Muriwai Beach when she was younger and Carissa had developed a lifelong fondness for that area.

"She enjoyed walking and running there, especially in the Woodhill Forest area."

Avison wasn't known to abuse substances or alcohol and had no diagnosed mental health conditions. She'd never sought help for depression or anxiety.

From a young age, around 11, she started to refer "not infrequently" to her intention to end her life.

Her GP noted in 2012 that Avison was a "worrier" and had "trouble handling stress".

Family members said after her death she was unpredictable and "very vulnerable, emotionally immature and lacking in confidence and self-esteem".

They said she tended to make things up that never happened and one even described her as "scheming and attention-seeking".

Coroner Borrowdale concluded while Avison had no mental health issues, she had not developed "mature ways" to respond to interpersonal and other stressors.

One thing that did cause Avison stress - aside from ongoing family frictions - was her finances.

She spoke to many people about her money worries, saying she was desperate to reduce her debt and move overseas to the UK to live and work.

Carissa Avison as a child. Photo / Facebook

She told family, friends and workmates she owed upward of $27,500 and at one point she took on extra shifts and worked with an employee assistance programme on a plan to pay it back as fast as she could.

Coroner Borrowdale outlined Avison's financial situation in depth in her findings.

Avison told various people that part of the reason for the debt was a relative had "stolen" money from her.

That caused friction within the family.

"It is quite clear that Carissa's financial predicament and the reasons for it that she disclosed to others - true or not - contributed to the ill-feeling that existed within her immediate family around the time she died," said Coroner Borrowdale.

In the week leading up to her disappearance Avison seemed okay. A friend she spent time with said she was "in good spirits and happy".

They spoke about Avison's plan to pay off her debt and travel to Europe.

A similar conversation was had with her mother.

She argued with her father and brother about money but given that was commonplace neither were they more worried than usual.

Avison later told a cousin she planned to "just stay away completely and avoid the drama".

She told another relative she would "just leave it alone and walk away from it".

"I think it would be wise for me to completely stay well away from (my family) and just stick to my original plan of saving up and getting out of here," she messaged him.

Carissa Avison, 21, was reported missing after she failed to show up at work. Photo / Supplied

The day Avison died, her flatmate suspected something unusual. She usually left for work by 6am but was still at the inner city apartment at 8.30am. The flatmate asked Avison if she had a day off and the 21-year-old replied that she was leaving for the office in five minutes.

She never went to work. She deleted her Instagram account at 8.38am and then took an Uber to a store. Staff told the coroner she was "happy and bubbly".

The last image taken of Carissa Avison before she died in early 2017. Photo / Supplied

"And that description is borne out by the footage from CCTV cameras that I have viewed," said Coroner Borrowdale.

Police later released the last image of Avison, wearing a white T-shirt black three-quarter length pants with black Nike shoes as they started their search for her.

Carissa's body was found by a couple out walking their dog near Muriwai Beach. Photo / Facebook

Avison took her purchase and ordered another Uber. She asked to be dropped off at Muriwai Beach.

The second driver described her as being in "a normal mood".

When she got out of the car at 10.40am he watched her walk into Woodhill Forest up a track.

Two days later, after Avison failed to show up for work twice, her team leader made contact with her flatmates. It was unusual for Avison to be a no show at work, or to go away without letting her flatmates know where she was and when she'd be back.

The team leader contacted Avison's brother and friend. The brother said he'd heard nothing from her for several days and had reported her missing with police. The team leader made a second report.

The search for Avison began.

"There is no evidence that Carissa took any food or supplies with her into the forest, and she was not seen by any person while in there," said the Coroner.

"Taking all of these facts into account, I find that Carissa is most likely to have died on that day she was last seen alive, Thursday 26 January 2017.

"I am satisfied that Carissa … (had) the intention of taking her own life … I am of the view that her death was a suicide."

She said Avison's early and tragic death had "a profound and devastating effect" on those who were close to her.

Muriwai Beach, where Carissa Avison was dropped off the day she died. Photo / Alex Burton

"In making my findings, I have had the benefit of a great deal of personal information that was not available to family, friends and colleagues at the time," she said.

"I have explained this evidence as it relates to Carissa's actions so that in retrospect it is now possible to understand some of the motivations that Carissa may have had for acting as she did.

"In these findings I have not set out to resolve conflicts … but rather to identify how various emotional and financial drivers were operating on Carissa's mind when she took these tragic steps to end her life."

Coroner Borrowdale said suggestions had been made that Avison had been "ill treated on social media" which was "implicated in her death".

"However the information I have seen does not establish that Carissa was abused or humiliated on any social media forum that was accessible to others - and I have not seen evidence that Carissa was subjected to degrading private treatment on social media messaging platforms.

"I have not found that social media was contributory to Carissa's death."

WHERE TO GET HELP:

If you are worried about your or someone else's mental health, the best place to get help is your GP or local mental health provider. However, if you or someone else is in danger or endangering others, call police immediately on 111.

OR IF YOU NEED TO TALK TO SOMEONE ELSE:

• LIFELINE: 0800 543 354 or 09 5222 999 within Auckland (available 24/7)
• SUICIDE CRISIS HELPLINE: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• YOUTHLINE: 0800 376 633 ,free text 234 or email [email protected] or online chat.
• NEED TO TALK? Free call or text 1737 (available 24/7)
• KIDSLINE: 0800 543 754 (available 24/7)
• WHATSUP: 0800 942 8787 (1pm to 11pm)
• DEPRESSION HELPLINE: 0800 111 757
• SAMARITANS – 0800 726 666.