Main VA MS site
http://www.va.gov/ms
VA MS Benefits site
I have included a portion of the text, but note the first sentence I put in bold... I am not sure if they mean treatment of MS or treatment of any condition, but if you are not SC, it looks like you have an option for free treatment of it.
http://www.va.gov/ms/multiple-sclerosis-veterans-benefits.asp
The VA provides health care services to Veterans with MS from the time of diagnosis throughout their life, whether or not they have a service-connected or non-service connected status. If an individual had symptoms of MS in the military, or within seven years after honorable discharge, he or she may be eligible for service-connected disability. If this is the case, the Veteran should complete the Veterans Application for Compensation and/or Pension available online (http://www.va.gov) or at his or her local medical center. Veterans Service Organizations (VSO), such as the Paralyzed Veterans of America, Disabled American Veterans, Veterans of Foreign Wars, and United Spinal Association are good support resources.