I have always answered very close to the truth. I don't drink often because I am afraid of becoming an alcoholic. I don't use drugs because I'm afraid of losing my VA/retired benefits. I have other escapist behaiviors like spending the day in daydreams, or online gaming all day, every day...
I am assuming you retired from the US Military, if so, then my VA specific comments will make more sense.
First, I too am retired (US Army, 27+ yrs), and VA rated service connected disabled (100%). PTSD is only one of the things VA has rated me as having, I also have a boat load of real physical ailments too.
You say that you "always answered very close to the truth". That COULD be part of your problem with the VA. Don't be "very close" to the truth, let it ALL hang out when talking to them. It will have two important benefits for you. First, and most important is that it will let them know just where you are coming from and just what it is you have so they can then give you the correct treatment regimen. You not being fully truthful has caused them to have an imperfect diagnosis which leads to an imperfect treatment. Second, when being evaluated, your honesty and full disclosure is crucial for them to be able to give you the rating you truly need.
While I am not saying to become an alcoholic or drug addict, you are mistaken in your belief in that becoming one will be an automatic end to those earned benefits. Truth is, if it did ever happen (and I pray it doesn't), the VA has multuple locations and programs to treat that too. Most Veterans who end up needing those treatments need them because of trying to escape / overcome / forget / deal with issues that are Service connected, so VA takes them in. Also, if you are in Category 1 (50% or higher, I think. Check their website), then you can get treated for anything, Service connected or not, by the VA. Check their website or call them for verification.
There is only one thing that will cause a loss / suspension of benefits and that is incarceratio, and I think you get them back once you are released. Once again, check directly with VA for verification.
My brother is an alcoholc, but has been sober for over 20 years. He now works with substance abusers and has provided my with a ton of information over the years. The big thing to remember in addiction is not to look at "how much" the addict / abuser is doing or using, but to look at the effect it has on the individual. If quantity were the only criteria, then the person who only had 1 drink on Friday night would not be an alcoholic. However, if that person is constantly thinking about it and counting down the time all week until they can have it, then they MAY be an alcoholic. That is a greatly simplified example, and it is a much more in depth process to determine / diagnose, but you get the idea. That being said, look at the effects on you by going online and daydreaming and the effects on you when you can't do it for whatever reason. Addictive behavior is addictive behavior, and none of it is healthy. Talk with your therapist about the effects, not just the quantity.
Bottom line, I understand how dificult it can be to tell some VA head shrinker what you got going on inside your grape, but you have to do it. You have to do it for the reasons I laid out above. Full disclosure with your therapist is a requirement if you really want to be able to deal with / overcome this crap.
BTW: 11B4P Master Blaster, CIB, EIB, standard fruit salad.