I know it is hard to imagine that one broken hip could lead to such a change in function for your mom. It is often the case that one broken
hip or other major surgery or medical illness can tip the scales toward a big decline in function for an elderly person when one is already in a fragile state of health. And as you referred to, a person's cognitive status is an important piece in walking safely and recovering from such a big surgery. Safe judgment, the ability to process and motor plan, memory and motivation are all cognitive functions that are important factors in recovering and re-learning how to walk. I never say "never" in my profession but the more time that passes without your mom progressing in her mobility, the less likely it will be that she will be able to walk independently. However, two weeks is still early to make such a long term prognosis. I would recommend that she continue to work with therapists and perhaps have a family member or caregiver trained in the exercises so they can help her do them daily. Finally, it is important to make sure she has good pain control and that her medications are reviewed to rule out any other reason she may not be recovering as quickly as you'd expect.