I am sure I am not alone in finding the ending of this excellent tale to be rather disturbing in the way it represents a compelete abandonment to the madness and lunacy that we see the narrator has been sliding towards throughout the story. The way that the narrator explicitly identifies herself as the woman that she has seen trapped behind the "bars" of the yellow wallpaper is made clear by her action of circling the room, following the wallpaper round and round. She, just like the woman she has seen behind the wallpaper, is trapped inside the endless maze of her own lunacy, and even the presence of her husband's body in the way of her course does not impede her movements. Note what she says to her husband and how she responds to his fainting:
"I've got out at last," said I, "in spite of you and Jane! And I've pulled off most of the paper, so you can't put me back!"
Now why should that man have fainted? But he did, and right across my path by the wall, so that I had to creep over him every time!
The narrator's lack of self-awareness and empathy is shown by her questioning why her husband should have fainted. What to her makes perfect sense is only greeted by horror and stunned amazement by her husband as he faints. The move of the narrator from being sane to insane is complete, and is marked by the narrator becoming the woman behind the wallpaper that she has imagined throughout the story.