CBT can be a very effective therapy......for certain people. The advantage of CBT over many of the other techniques is the timeline for seeing change (which the insurance companies want). The disadvantage is that it often one deals with the first level or two of issues. It lacks the ability to really get down deep because the exploration and solution to an issue aren't merely a definable cognition / behavior, but a more complex interaction of a number of variables, many of which are not clear.
Are you part of a vietnam veteran's support group? Vietnam (as you know) was a very different war for everyone involved. War is horrible enough, but when you roll in misinformation, spotty support, and a failure to acknowledge the real sacrafice of the combatants.....the results can be catostrophic for those left to battle their demons alone (figuratively).
I will not pretend to know your story, but I do have a few suggestions that may help. First off, you need to eventually find an active vietnam support group. I say eventually because you may need a bit of time to 'find your story' because a support group can be helpful. In many cases of trauma (whether it be from a sexual/incest survivor, war veteran, domestic abuse survivor, etc) a person loses their story. The truths that happened are buried amongst the feelings of shame/rage/depression/etc. Finding your story story, and subsequently being able to tell your story, are important steps in the healing process.
I have listed two books that may help you frame your story. The first one is by Judith Herman, who wrote a ground breaking book about the REAL consequences of various types of trauma (the same ones I listed above), and how we misinterpret how trauma effects our lives.
The second book is by Tim O'brien (who you have probably heard of, and may or may not have read). He has become a voice for soldiers from vietnam. His way of telling his story was through writing. To be able to tell his story, he ties in both fiction and fact. Just because he uses fiction doesn't make his stories less true, in fact they help tell the true story because he is able to get it out there to people, to try and help them understand, and in the process.....also help veterans understand part of what happened.
The Things They Carried , by Time O'Brien
Trauma & Recovery , by Judith Herman
I wish I could write more, but I have a plane to catch. I'll check back in tonight and write some more.
-p