Dear Fiona,

I think your friend needs to see a skilled LC - she's doing a great job, sticking in, under difficult circumstances. It sounds like, ith the pain, she is not able to feed her baby often enough/long enough, and the baby's weight is suffering.
In terms of breastfeeding, she just needs to keep feeding. If it is really too painful to continue, she might consider trying a niplple shield, or if that is unsuccessful, expressing for a day to rest the nipples. for this it would be best if she hired a pump from the Australian Breastfeeding Association, so she had the support of trained counsellors.
In many cases these sorts of problems are not thrush at all, but a staph infection. The symptoms can often be very similar. You often here of thrush infections that go on for months - but I think in those cases it is usually a staph infction, misdiagnosed so the mother is actually following the wrong treatment plan