Hi Steven. Welcome to Sailnet.
Yes, there are quite a few opportunities for sailing. Walter Reed has a program in conjunction with National Sailing Hall of Fame in Annapolis as well as various sail and yacht clubs on the Chesapeake that takes vets sailing through the Wounded Warrior program. There are others. I was at a meeting a few weeks ago with a gentleman who mentioned he was involved with the Wounded Warrior sail and was coordinating the next one. I should have paid more attention.
Chesapeake Region Accessible Boating
(CRAB) hosts vets for Wednesday sail races. Racing is a fantastic way to gain sailing skills quickly.
More than likely others in the forum have more information for you.
Best of luck and let us know how you make out.