Please try to convince your mom to take her to the vet. You need to know for sure what's going on so you can handle it correctly.

Glacier said exactly what I would have said (but put it better than I could). My dog, Bear, was blind for the last 5 years of his life and did very well. His cataracts were from diabetes.

If her hearing is also going, walk hard when approaching so she can feel the vibrations in the floor.