Welcome to the forum Blue, it is always lovely to have new members. Aloha? Are you from Hawaii by any chance? If you are I am quite envious, as the weather here in Newfoundland has just become cold once more!
I believe you will find many here who relate to your story, and will understand your anger and frustration. My personal story is a little different. Although I am a military wife, my husband does not have PTSD. Rather one of my sons, who was also in the military, had it (he is sadly no longer living), and my stepdaughter Evie has it as well.
I am not certain there is a definite next step to take Blue; each situation is unique. Unfortunately you cannot force your husband into treatment of any kind, though obviously that is what he sorely needs. My Evie ran away from us for 5 years, refused contact with us for that entire time, though we were constantly searching for her. We have her back now, and she is in treatment, but we had several years of worry where we basically had to let go of her and hope for the best. I would like to say we handled it well, though the truth is we certainly did not.
As difficult as it is, try to give your husband the space he requires. After being apart from you for a time, he may change his mind and come back to you, however if you push too hard now, you may lose him permanently. I am sorry I don't have anything more concrete to say; perhaps others will have something specific to suggest. The bottom line: it really is up to him to receive help. At the very least he should be seeing a counselor or attending a support group. You may suggest this to him, however he likely will not do it until ready. Try to keep the lines of communication open with him if he is willing.
This forum is very supportive and an excellent place to learn about PTSD. Read as much as you can here, post and ask questions, and speak with others. It will help. Also try to concentrate on your own happiness, and that of your children. If you are like most of us, you spend a lot of time concentrating on the feelings and needs of the PTSD sufferer, and neglect your own needs. So be very kind to yourself. Do something nice for yourself today! Once again welcome.