You may wish to check out EMDR therapy Eye Movement Desensitization and 
Reprocessing therapy.    My wife and I both developed Post Traumatic Stress 
Disorder (PTSD) some time after our son was suddenly killed 9 years ago.

We each went to a therapist for grief counseling and therapy.  Eventually I got 
to the point of being able to move on in my life, but my wife got stuck.  They 
used the EMDR with her, and it made a very big difference.    As I understand 
it,  the desired goal is to stop the constant memory of the traumatic event 
from replaying itself over and over in the patient's brain.    EMDR did a good 
job of this for my wife.   

Neither one of us has PTSD any more, but at the same time, you need to keep 
thing s in perspective.  Losing a child suddenly like this will always affect 
your life forever, and it's not like you ever 'get over it.'   But you can get 
to the point where you can lead a relatively normal life.  

Steve