After her HSC, she moved to Sydney for study. But it happened again.

More hospital. More tests. Eventually, she was forced to return home to recover.

She had always been part of a loving, Christian family, but her frustration was making it hard to communicate.

"My mum suggested I start to journal my feelings," she said. "This was a way of getting in touch with myself and what was going on inside me.

"A few years later, I was married. A few more years later, I was pregnant.

"But my mystery illness came up against me. My son was born five weeks early and whisked away. I couldn't hold him because he was in a special crib.

"Coming home from hospital, I felt God was saying to me, 'Write down what you're going through'.

"I didn't realise 'til months later that what I'd written was going to become a book. Once I had realised that and written it down, I sensed that it was my moment to move forward and become a stronger mum."

The book is called Invisible Illness - Finding God's Healing. It is set out as a set of short daily readings from Mim's journal, followed by two questions and space to write your own answers.

Mim is deliberately non-specific about her illness because she wants the book to speak to all people who are battling. The book can be accessed through www.melindalouise.net

"Through publishing my story, God's taken me on a journey to be stronger with him," she said. "I hope my story can help others to take courage."