Interestingly enough as hard as it may seem, you may want to have it be their idea. How do you go about doing that? Well, you know that if you were to go after it with an agenda, they are gonna see right through to it. Before asking them anything, take a look at their point of view. Maybe they are fearful of the change, not knowing the outcome can be very frightening to many of us, regardless of age or how long we have lived in a place. Maybe they are having a hard time admitting their lowered energy level. Maybe they don't care if the place is not maintained and they have priorities else where. Find out where they are coming from before moving forward with too much too fast.
Next, what about asking them open ended questions about their situation? You know: How are you going to make that work? How is that working for you? Remember it takes a curious and loving heart to deliver these questions in a manner that is non-judgmental. If they feel judged or pushed, they are going to resist you even more.
Regarding the 'What is': well ask her straight out. What if you fall? With her answer respond, lovingly: "How is that different than if you fall here?" Let her express her concerns and continue with validation of each of her concerns.
If you come from a place of non-judgement and understanding, they will, with your assistance, be able to move mountains.
Let us know how things go.