Are you doing the best you can?
Knowing you, the answer is yes. Then nothing else can be expected or required of you. These are your mother's last days, not yours. You take care of her. If it is important to you that you be closer to her or there is something that you want to do with her for yourself, then do it. If not, then it is her responsibility to spend her last days as she needs. Even though she is infirm, there is part of her that is control of her life and her destiny. The same can be said for all of us. But again, this is when it is seen from that higher perspective.