A troll sent Olivia a disgusting message online. They weren't expecting her to write back.

Thursday September 13 is R U OK? Day, a mental health initiative aimed at starting conversations and preventing suicide. To learn more, find resources or find out how you can help, visit the R U OK? Day website. Don’t forget to ask the people around you how they’re doing, not just today, but everyday.

Olivia Rogers was about to go to bed on Tuesday night when she decided to quickly check her Instagram messages.

The 26-year-old former Miss Universe Australia was scrolling on her phone, sitting on the toilet, as you do, when she opened a message from someone she’d never met – the most disgusting, hurtful message she’d ever received.

“My jaw just dropped, I thought ‘what the hell, I can’t believe someone has written something so awful’. I was shocked,” the speech pathologist and artist told Mamamia.

“The DMs [messages on Instagram] are quite constant, the majority are really nice, people wanting tips about hair or recipes, but to come across this one, I was shocked.”

Among other things, the troll told Olivia that no one actually cares about her anymore, that she’s “wooden and fake”, that no one is buying her “anxiety bullshit” and that she was never going to win Miss Universe because she’s “too fat with no tits”.

After re-reading it to “try to process it”, Olivia showed her boyfriend, then decided to write back.

"My boyfriend said I shouldn't give the troll that, but I wanted to be diplomatic and let them know they can't just get away with that and speak like that, and be so awful and not be held accountable," she said.

"I always respond, I didn't want to name and shame because I don't want them to be attacked for attacking me, I just wanted to remind them that I'm a real person with feelings and what they say has consequences.

"I wrote my response in two seconds and sent it, and then decided to share the experience on my Instagram story."

By sharing the message, but mostly her response, with her followers, Olivia wanted to make clear that cyber bullying behaviour like this on social media isn't acceptable.

"Most of those words didn't upset me, I didn't shed a single tear and it rolled off me this time because I'm comfortable in my own skin and happy with who I am and I know it's not personal, but I wanted to share it because years ago, it would've affected me," she said.

"I know something like that would affect so many people, and that's what scares me the most. I'm lucky I have thick skin and it doesn't upset me, but so many of my friends said they would've cried themselves to sleep because it was so awful."

Olivia did admit she wasn't able to brush off the entire message. The stuff about her appearance didn't affect her as she "knows that's just not true", but as someone who speaks openly and candidly about mental health on her public platform, the comments about her "faking" her mental illness really cut.

"The bit that hurt the most was the 'not buying your anxiety/depression bullshit' because I know myself, and that I was really sick in my teenage years. I was suicidal, I've touched on the fact my dad has bipolar and there are things within that that were horrible that I'm not willing to share because that's his story and really personal, so for someone to say that they're 'not buying it' is hurtful."

"They also said 'have you been through this, have you been through this' about other difficult things people go through... a little part of you doubts yourself and thinks maybe what they're saying is true. Mental health has kind of become a competition about who's had the worst experience, it shouldn't be like that.

"I'm not saying that I've had it bad or that I've had a shit life, but I have struggled. You don't know anyone's complete story, and mental health doesn't discriminate. It doesn't care what your background is, it doesn't care what you look like, what your occupation is, it's irrelevant. Mental health isn't a competition."

A post shared by Olivia Molly Rogers (@oliviamollyrogers) on Aug 17, 2018 at 7:37pm PDT

Instagram has over one billion users worldwide, many of those being children as young as 10. One in four of those young people say they're bullied every few weeks, one in five say it's online, Bullying No Way reports.

People who have a following, like Olivia, receive countless private messages. While most of the hate Olivia receives can be found in the comments section under her photos - "mean comments like 'you look gross', 'your tan is patchy', 'I don't like your hair', stuff like that" - she said abusive messages where someone has gone out of their way to hurt you do stay with you regardless of how thick your skin is.

"It always plays on my mind about Charlotte Dawson, [trolls] are the reason she took her own life. They might think their message doesn't mean anything, but it does mean something."

"Out of the hundreds of thousands of nice messages you get, it's those awful ones that stick with you. You can quote them word for word."

The majority of Olivia's followers are women in their early twenties, and by sharing her experience, she wants to remind people that's it's really not OK to send someone you follow a thoughtless mean message online, but also that social media isn't real life.

"If I was by myself when I received that message and didn't share it and kept it to myself, it would've really affected me. So be open and talk about it, talk to someone, talk to your support network. Talking about it in real life out of the context of social media helps to put things perspective, and starts these kinds of conversations."

"They say don't read those messages, but you can't not. Just try to remember what's good about you, because it's not about you. It's about them."

Olivia is an ambassador for Liptember and Women's Mental Health. 

If you or someone you know is struggling with bullying or their mental health, please seek professional help or contact Lifeline on 13 11 14, Kids Helpline on 1800 55 1800 or the Suicide Call Back Service on 1300 659 467. If you're in immediate danger, call 000.