This drives me, and my wife, crazy sometimes. She tells me to go to the store for bread, eggs and cheese and I come back with bread, eggs and ?????. We now use the memo pad feature in our blackberry for me to make a list so I don't forget something, or get something we didn't need. That is just one example of the many ways in which my short term memory has been affected. My psychiatrist says it isn't really a memory problem but a concentration problem. My hyper-vigilance is probably one of the main reasons I have this aspect of PTSD as bad as I do. I am constantly on alert and trying to maintain situational awareness for threats (27+ years in the Army will do that to a person sometimes). The driving thing can be stressful too, especially since I now live in Panama and EVERYONE has to be hyper-vigilant on the roads here because of the traffic and road conditions. One thing to keep in mind is that you have started on the path to overcome this because you have identified the problem.