Try a product called the foot flexor. This is a fantastic device used by elite sprinters to encourage dorsi-flexion without statically fixing the ankle. I use it all the time with neuro patients however do not know of anyone else that does. All my patients have done extremely well with this device. It seems to me that she sounds like a bit of a "pusher" and probably needs more proximal stability work arount the hip joint with regards to her long term progress. I do agree with short terms assistive devices as long as the medium term goal is to do without them. :-)