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At the age of 21, Sydney water polo coach Lilie James had the world at her feet.
She led a busy life with university study, part-time jobs, nights out with friends and time with her family.
But her life was cut short one year ago when she was murdered by her ex-boyfriend Paul Thijssen while at her workplace at St Andrew's Cathedral School in Sydney's CBD in October 2023.
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Thijssen, a former student of the school, had also been working there as a sports assistant. His body was found later at Diamond Bay Reserve at Vaucluse.
One year on from Lilie's death, the suffering remains raw for her parents Peta and Jamie, who have been left completely heartbroken by their daughter's absence.
"If you knew what he did that night, I think you'd understand why we can't forgive what he did," her mother said.
"I don't think you can wake up one day and do something that brutal," her father said.
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The two have opened up about their grief in an upcoming interview with Tara Brown on Nine's 60 Minutes to raise awareness of the domestic violence epidemic.
Brown said it was clear that Lilie was "a girl you couldn't stop" and her parents wanted more time with her.
"She was so busy, she was studying at university, she had part-time jobs, she was a part-time water polo coach at St Andrews, she was dancing, she was going to netball, she was partying with her friends," the television presenter said.
"She had a very full life but one that you would hope for for a 21-year-old."
Brown said Lilie's parents hadn't met Thijssen, which spoke to how casual the relationship was.
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"They didn't feel that Lilie felt the need to introduce them, it wasn't that serious," Brown said.
"Lilie's parents certainly talked to her about him and they weren't concerned at all.
"Lilie's dad Jamie got a text message, which was supposedly from Lilie calling him to the school to collect her, that she was in some sort of trouble.
"It's now believed that text message was sent after she had been killed by Paul Thijssen.
"One can only speculate why he wanted Lilie's dad Jamie to go to the school.
"If he had gone further into the gymnasium, what he would've seen and those images, he would still be trying to recover from now."
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An coroner's inquest due to begin in March next year is expected to provide more answers on the 21-year-old's death and details about the person Thijssen was.
"We've spoken to a forensic psychologist who believes Paul Thijssen most likely suffered from a narcissistic personality disorder, which meant he was always potentially capable of something violent," Brown said.
"He would've felt so injured by being rejected.
"It was a casual relationship that only lasted five weeks, it was something they both went into understanding it wasn't ever going to be serious, it was just about a bit of fun.
"When Lilie ended it he could not cope, he would've been filled with incredible rage."
Watch the full interview on 60 Minutes at 8.40pm this Sunday.
Support is available from the National Sexual Assault, Domestic and Family Violence Counselling Service at 1800RESPECT (1800 737 732). Readers seeking support can contact Lifeline on 13 11 14 or beyond blue on 1300 22 4636.
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