My interpretation is different. The guy, whose name she initially doesn't remember, says he'll always be with her at the end. To me, this hints that he's a BF/husband that she lost and tried to forget. She's locked herself away in grief, eternal night, not wanting to deal with it. The sacks are her good memories (including those of him), with the sacks she hasn't opened being future good memories she's waiting to have. The room full of oddities is just the dross of her regular life. Going deeper, there's comfort in her childhood rooms, but fall back into those rosy memories, and you'll never escape. The mannequins -- perhaps all the people around her, who failed her, or offered her comforts. Rage against the world in the face of her loss (which she doesn't remember till the end).
The old lady is a bit puzzling for me. A stern figure who gives her tasks to do, who, at the end, she realizes "was never there at all". Someone holding her back, telling her what she should be doing, perhaps someone in her life saying she still needs to keep up the house in her grief, etc. And at the end, she sets herself free from the cage she's created, remembering the good in life (and him) and moving on.
Anyway, by far my favorite story in the volume