Your experience was horrible, and it was not the worst of what could have been. But, it is a fight of your fear, working against you. It might be possible to gradually change it.
During the day, when you are not tired, picture the best possible Iraq ten years from now. You have not sneaked into Iraq; picture yourself as an invited guest. Invited by Iraqis who want to show you the Iraq you could not see while you were there, you are a welcome person.
For the first time in decades, you can walk along the Tigris with no fear. You could (mentally) visit the museums and view the artifacts of the centuries. Picture the Hanging Garden restored, but with a new beauty unhampered by bricks with names. Picture haggling in the marketplace. Taste your favorite foods, while imagining the best Iraqi restaurant.
Picture your homeland in the best possible view, without fear. Continue to imagine a new and wonderful Iraq, far beyond the vision you could have imagined while there. Change a nasty thought to a pleasant thought during the day. When fear flashes into your mind, change it to something better. Or, picture a ZAP BUTTON, zap the flashback away.
Then when you wake up from a nightmare, change it for the better in your mind. Try to change the nightmare to a dream, and then to a pleasant dream.
It may be worth the try. Picture Iraq as it could be, as it may be ten years from now.