How do I tell my mother who is fearful of death that it is time for hospice care?

My mother has broken her 2 hips, ribs, back, and wrist in the last6 months and is nolonger eating much. She is 89 years old with severe osteoporosis and currently in a wheel chair. She has little strength for rehabilitation but continues to want to use a walker again which is pretty unrealistic considering her state of failure to thrive. The social worker said it is time for hospice but my mother wants to continue rehab to be able to walk with a walker. She is too frail to do this. She is afraid of death and I think if she was told she was going into hospice , she would loose her will to live.