She and Her Cat: Everything Flows

After her roommate moves out, it is just her and Daru.

When she hits the lowest point in her despair, Daru wishes for nothing more than to be of help to her; his aging body just won't obey his mind the way it used to.

She has kept herself locked in her apartment and ignored phonecalls for so long that her friends and family; mysteriously, her mother receives a phone call from her home number, but only hears silence on the other end.