To do everything you do, you must love your dog very much. May i suggest one more thing. Try swimming - dog hydrotherapy.
See if there is a pool near you and ask them what they think. Swimming is a weightless form of exercise and once you have done a couple of sessions with the hydrotherapy centre, maybe look at ebay and buy a 'dog life jacket'. To help you save costs and the fact your dog is a small dog - you can easily swim your dog yourself, simply by filling up your bath at home and swimming her in there.
Its infact very simple. You place a a little step on one side of the bath. Place your dog in the life jacket. They will always come with a handle at the top. Place her into the water and teach her to swim towards the step. Very quickly she will build up muscle. S
tart by 3 sets of 1 minute a day with 5 minute rest breaks in between. Do this for 2 days, then nothing on the third day. Then do another 2 days and give her the other two days off. The days off are very important. Slowly increase the swims times over a period of 4 weeks to build up to 10 minutes a day.
I have treated a lot of dogs (swimming) with neurological problems and this really does help.
There is something else that may help - this helps all sizes of dogs that are unsteady on their feet. The harness helps dogs from all sort of things; Hip dysplasia, cruciate ligament injuries, chronic degenerative radiculomyelopathy (CDRM), Spinal, etc - basically it helps with any problems to do with walking.
These pictures show a very big dog, however, like i said, it works on all types of dogs. I thought you may like it as it help you walk you walk. Its made in the UK but shipping is anywhere in the world.
Good luck - and i really hope this has helped - please do try the swimming and let us all know how she is getting on 4 to 5 weeks time.