PTSD is normally brought about by a change in a live. Something that shocks the system ( so to speak ). No doubt your granddad was close to you and his passing had an effect on your life. At least you seem to know where and when it all began. That is good if seeking help. Saves them going over your whole live and trying to dig up things. I assume you are getting help for your situation? If not it may be a good idea. Be it grief counciling if you feel the death is still effecting you or CBT if you think something started it all off. But the death also played a part. CBT would be a wider range of theraphy. It would also teach you ways to cope when anxiety kicks in. Minus the alcohol, which would only serve to highten your anxiety at the best of times. It sure isn't the cure. But there is help out there. Just a case of searching out places and finding the right kind of help for you.