welcome to the boards, but - sorry that events have conspired to bring you here.
Military life, tours of duty, etc, seem especially conducive to the situation you have described.
Your first task is to try to take on board that this is NOT about YOU. It is about HIM and there is little or nothing you can do to change him. However, there is much you can do for yourself - and in doing so you are more likely to make progress with your M. I counsel you to seek support immediately from friends, family, and here on these boards, where many wise heads congregate. Read the postings here, and get the books Michele has written, espectially DR. Place faith in your higher power. Your H is on a journey of his choosing. Don't pursue him. Devote your energies for the time being on yourself and your children. You will be amazed at the results.