'suffocate' is on my favourite words list. so is Asphyxiation. I like the alliteration you used there, suffocating silence, and again with sewing and souls, and cast ..key. wheteher you have actually intended it or not.
I like these four lines. You don't need to add. Here again, I like the open spaces, they create something mysterious.. what has happened?
Short poems will get short comments, sorry I cannot think of anything else to say.