Because she was pregnant, she was unable to start treatment.
"The doctors were unable to treat me with the disease-modifying drugs I needed because they would harm my baby.
"While I tried to face the diagnosis head on, I had weakness in my legs, my balance was awful and my eyesight worsened."
Miller got through her pregnancy, giving birth to a son, Lucas, in March 2013. But two days after Lucas' arrival, Miller lost feeling in her legs. "I was paralysed from the waist down. It was simply terrifying."
The type of MS affecting Miller means her symptoms are sporadic. Her pregnancy led to damage of the nerve fibres in her brain, which caused her paralysis.
Beginning treatment immediately, her newborn son was unable to stay with her in hospital. "When I started receiving alemtuzumab, I got really cold, my eyesight got worse, and I was dealing with all of this with a new baby."
Miller says being unable to look after Lucas in those first few weeks affected her ability to bond with him.
"I gave Lucas a bottle once a day, if that," she said. Breastfeeding wasn't possible because of her treatment.
"There were days I was too tired to spend much time even holding him. I wished I could have given him the cuddles that a mother should give their newborn child."
After ongoing treatment and extensive physiotherapy, Miller eventually learnt to sit up and stand again.
Just over a year later she was able to walk, at first aided by a zimmerframe, then crutches.
Now back home with her husband, Graeme, and her son, she's doing her best to be the hands-on mum she'd pictured herself as.
"I'm okay day-to-day, but I still can't walk like I once could,' she said. 'I still struggle to stand for long periods and can't carry Lucas for long distances. It's tough, but I am determined to get better for Lucas."
- nzherald.co.nz