Home is where the heart is, and in this occurence, where your Grandma is.
She loves you so much, but an old lady is someone who also needs the nurturing that she so easily gives to you, isn't that right? Therefore, when she becomes too fragile to go out, you can be the support she needs.
Help her find what she needs, run little errands in the woods, but be careful as the hunt for resources might become a hunt for... you?