This one hit hard because while i don't understand what you are going through i understand the message within my own pain and past. I truly love your poetry so much. I have nominated this.
The first thought that came to my mind when i read this is, you wrote in the point of view of a heart but i also think it is deeper than that. A shattered heart that was split into shards and after that into more shards that were left like into a corner and abandoned.
They are worthless to this person who hurt you but they got it into your head they are worthless to you too and with the shards they cause you to ache in pain.
This person is a shadow metaphorically because you see them as that way. They broke the person you were and they wanted you to be.
All the pieces are now ink droplets on your poetry. The very poetry that helps you heal.