The speaker feels hollowed out by giving too much of herself to other people. She says she handed her soul to a "passive ghost" and now stands under a lamppost, looking for light while hiding it herself. That contradiction sets the tone: she wants to be found but keeps holding back the very thing that would help.
She describes breaking her heart into identical parts and handing them out to people she admires, almost as if they were extensions of her. Now she blames only herself, since she knew she would never be whole again. Her cry in the fifth stanza, that she would have to shout for the world to hear her, shows how badly she wants to be understood.
The mood is wistful and quietly desperate. By the end she sees herself as ruins, "fiber by fiber," and compares herself to a dried lake's sandy shore: something that once held water and now holds only emptiness.