Thanks sqad for pointing me here. The actual problem is not one I have experience of but while your daughter is getting the answers she needs there may be things that can happen to make her life easier. has she still got good movement and strength in her legs? If she has then she can retrain to walk visually doing without the feedback that the nerves would give you and I, somewhat like an amputee would, The right walking aid will help immeasurably and the physio should be able to prescribe this. She should be getting assessment and treatment NOW, make a fuss if she isn't.
The other option is to become a whole or part time wheelchair user if walking is not going to be possible or functionally useful. The wheelchair should come from the NHS and there are grants available to adapt the house and car so that she can continue to be independent and these usually come from the local council via the occupational therapy service there. Check that she is getting all the benefits and help that she is entitled to, I believe that MacMillan are helpful for this, if she isn't already in touch with them, you can just phone for advice.
I can only imagine the pain and stress that you and she are going through.
http://www.macmillan....elp/HowWeCanHelp.aspx
if i can help further please post again fao woofgang in health or on this thread.