"I am black and I am evil
I am death and I am misery
I am heartache and I am a disease
I am nothing and I am everything you don't want"
^^ Wow. This is a really good beginning. It makes me wonder what makes you think you are these things.
"I am every thought you question about me
I am every curse you think about me"
^^ This is deep. I like the actual feeling behind the piece.
"I am not even worthy of texting you
I am not even worthy of talking to you"
^^ WOO! I love texting, hahah. Okay, seriously, now -- Like I said previously -- I like how the piece is deep. The words are very genuine, and I like that.
"I wouldn't be worthy of breathing the air you breathed out
Stealing your air, I am a thief
I am no one important
^^ Hm. The first line -- I'm not a fan of, personally. "I wouldn't be worthy of breathing the air you breathed out" <--- Maybe you should change this line to something like.. "I'm not worthy of breathing the air that you're breathing". Only a suggestion, of course. However, I do quite enjoy the rest of the stanza.
Overall; I really liked this. It held a lot of emotion, I feel, and it was truthful and genuine.