This is a very serious journey you take the reader on. From the excellent way you described the blade as pleading for your wrist. To the composition of the letter, the contents within the letter are very direct. Overall has a good flow. I found the reference to the family photo very moving.

The last stanza reveals how hurtful words can lead to such acts.

Were you really serious while writing it or it's just a fiction?

I hope it's just a fiction or may be someone else story you wrote here.

See, I am an amateur here too, so I can't advice you or say what right or wrong, but one thing I can say that you write well and as Mark pointed out one of the best line of this poem.. I agree with him.

Keep on posting them.

I really feel for the narrator in this poem, because the saddest people always smile on the outside, but they are caged with sadness and anguish on the inside. The dark reality you take the reader on is simply well done. I feel the voice you have in this piece could make for a short story, to get more of your message out!