Have you looked into Hospice and respit care? It can really help out a lot and you can get assists. Being in the health care field I can understand what your going through I've taken care of a lot dieing people including family. You're in my prayers. I know it's hard but hospice or respit care can really help.
That is a great song..maybe what you can do too is put a whole album together of your family pics in one special album.. so you and Mom can look at all the pictures together when you get them in the album..she would enjoy that..