That is always a possibility. I think about this a lot. What helps keep me from dwelling about it too long is to look at it from a different angle. "Something could happen that makes me better." Life can go either way, good or bad, we can't change this. We just have to fight like hell to pull our minds out of the "What if..." spectrum of our brain and continue working with our present. Easier said than done for someone with very real anxiety from PTSD. It's a process, but it's possible.