Single Status Update
Have you applied to the VA Vocational Rehabilitation Dept yet? Even Vet's with PTSD @ 50% SC, might be determined by a Voc Rehab Professional to be Unemployable due solely to the PTSD SC. A Voc Rehab Denial Letter could help.
Then there's always the possibility that your really not IU. Your apparent historic Alcohol and Drug problems appear to be the real problem.
The VA Voc Rehab might be able to help find some sort of employment, where you really don't have to work with other people, possibly self-employment. There's a big difference when it comes to dealing with customers as opposed to co-workers.