Cassandra Grodd felt "unbelievably different" from her peers growing up, criticising every photo she saw of herself from the age of nine and consistently drawing unrealistic comparisons to others.
Struggling with anxiety prevented the 22-year-old from socialising, left her mind in constant disarray and triggered an eating disorder.
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"I remember for a school production we all had to wear the same dress, I stood next to my friends and I was the only one who had wide hips," she told Newshub.
"I was also one of the first girls in a bra. Everyone looked at me weird. As I grew older my anxiety manifested between spells of depression and a consistent struggle with bulimia and body dysmorphia.
"At one point I was too anxious to cross the street because I was so concerned about what people would think of me, I could hardly order coffee and before any social event I would have full scale break downs."
Grodd said she would have screaming matches with her parents and cry, smashing her way around the house in a frenzy that could take hours to recover from.
She had a "seriously rocky time" at school, switching her identity like she was "changing lip gloss", regularly switching up hair colours, fluctuating up to 10kgs in weight and handling social situations in bizarre ways.
She was bullied badly towards the end of her schooling.
"I think people never understood me, I didn't even understand myself. I went to university with basically no friends from school, they all went to Wellington and Dunedin but I stayed in Auckland mainly because I didn't trust my anxiety away from home.
"It wasn't until I was about 19 did my parents confront me about my bulimia which I'd struggled with since I was around 13."
At her worst, Cassandra was throwing up four to six times a day, in any location - even in planes.
She turned to taking medication to get through university after experiencing an extreme panic attack in her first law test.
"I fainted in my chair and literally ran out of the room. From that moment on I didn't sit an exam without medication until my fourth year of uni.
"My friends would even sit beside me in exams just to make sure if I passed out they could help me. It truly ruled my life."
Her battle with anxiety is something she believes New Zealand youths deal with more widely than is acknowledged.
"The thing with anxiety is when I say 'I have an anxiety disorder' or 'I struggle with anxiety' the first thing I hear back is 'same'.
"I don't just think it's common, I think everyone has it to an extent. It manifests in everyone differently, for myself it was in my relationship with food but everyone handles it differently.
"I think our generation is particularly struggling with anxiety and self-acceptance, literally everyone is paranoid of being the odd one out, of not being 'cool' but even the cool kids don't feel cool.
"Everyone feels left out, and I'm kind of like - of what? We all think we are so independently different and it's sort of like, um hello? As soon as we open up we are all on the same page.
"People need to start talking about the things everyone keeps quiet, and that's why I wrote the book."
Her anxiety disorder brought about a gruesome, raw and very unglamorous eating disorder which she has battled for the best part of a decade.
Bully gets its name from the word bulimia. It is her first book, which launched on Wednesday night.
"It came about because I started an Instagram for my writing about a year-and-a-half ago, my writing had enough interest that I decided to persue it," she said.
"It centres around the idea of beating yourself up, for instance when you are younger you are told to tell an adult if you're being bullied, but what happens when the bully is in your head?"
Her book opens with a story of her purging and then vomiting in the back of an aeroplane on the way to London.
"It was horrific and it was uncontrollable. I wouldn't even want the food but I would just keep eating. It was awful and it was intoxicating. I felt brainwashed by myself."
Bully is split into five sections and delves into her experiences with learning self-love, healing and growing up.
"It's essentially a long letter to the people suffering from different heart breaks - and the worst of all, those breaking their own hearts.
"I want the lost souls to be found and I want to make people find their happy. I want people to be understood. I want people to be confident in themselves.
"That's what my Instagram is about and it's also what my book is about, it's designed to give you the tools for you to find what you're missing and hint to people that everything they need the answer to is already inside them."
Ms Grood says she still struggles with anxiety, but it is a lot better than it used to be.
"I would never say I'm cured but I'm damn near close. If anything, I'm outrageously confident now. I've learned to use it to my strengths."
Bully is currently number 11 in best-selling poetry by women and number five in self-help for eating disorders on Amazon, and it's only been live for a day and a half.
"There's not enough help for mental disorders and also just not enough help for people right now," she said.
"I know a lot of kids go through the same thing and I want them to know they are not alone."