Stevie, I am hearing you on that one. The beast dug it's claws in they reckon during my last weeks of deployment, probably one body too many, one ied too many, or even the mortar or rockets, who knows.
The only way I managed to sleep was to find the black gate and go buy some illegal Jack Daniels, f*cking wrong I know, but when you are not in the bad lands, you have to be able to get some shut eye.
When I got home it did not take long to develop full blown PTSD and a full blown alcohol and pot addiction. Your right, you feel dead inside and sometimes I still do today.
It gets better mate and you are better off without the self medication. It will kill you.