Secret Ingredient: Cyanide

I've been seriously considering eating a tape worm so it can eat all of my food. 
I am at the point of desperation where I feel the world slowly fading into nothingness,
and a very large pit of despair and hopelessness expanding within my body. 
I think about overdosing on my medication and dying.  Instead, I take 4 and float along, being half awake.
I think about tying a noose around my neck and hanging myself. Instead, I hold my breathe in the scalding shower and get light headed and feel surreal. 
I think about sharpening the long knife in the kitchen and plunging it into my stomach. Instead, I puke up my sadness and cut bits of my scalp, so nobody can see. 
I am fading and I want out of this life. 
I am not happy. I am not successful. I am not strong. I am not skinny. I am not pretty. I am not smart. 
I am worthless and need to remove myself. I am a parasite. I drain all the good in a person, discard that person and then drain another, while waiting for the former to recharge and then drain until they are emotionally dead.
I want to know if a heroin overdose can be felt. If it can't, I want to do it. End everything. 

CJ