Hi Emma - Yes, there are very few Aussies on the forum at present. Welcome

I'll be watching for your posts.
At 65 your mum isn't too old for a transplant yet, if she doesn't have any co-morbidities which would mitigate against it. Sounds as though she's always been very healthy, which was the case for me too. I have never smoked or drunk alcohol and was brought up eating lots of fruit and vegies and pretty much dairy free. I follow a low-sugar diet too because low white cells/neutrophils/lymphocytes are my main problem. Even though I don't feel like it sometimes, I try to go for a walk in the fresh air every day. The main different thing I did was retire and take a long holiday about 6 months after diagnosis. I had a high-pressure job in the inner city (Sydney) when I was diagnosed.
Has your mum had her Vitamin D3 and B12 levels checked? I find that taking D3 definitely improves my platelet levels. Mine have been in normal range most of the time since I started supplementing.