I'd start the process now. Talk to VA, vets service organizations, and an attorney who works with social security too if that is an option.

You can start now. Report what you are going through. Find advocates and support. Get help figuring out the lay of the land - what is available, what the application process is.

In regards to social security, I didn't have to wait and build up a paper trail first, I started the application process, and social security sent me to doctors for evaluations. I eventually got a lawyer to help me through the process, I was denied the first time which many folks are. Lawyer made all the difference.

You don't need to suffer more in silence for years before applying. You can apply now.