My compassion to you both for having to walk this difficult road, which has no quick or easy answers.
My brother-in-law was a medic in Vietnam. I remember my husband and I going to a County Fair with my sister and her husband. Fireworks went off and my brother-in-law hit the deck, which in this case was the dusty ground in the middle of the fair. It was shortly after we met him, and I think it was really hard for him to have that happen in a public place. Another time, we were on a picnic and he got one of the recurring bouts of malaria he is subject to.
There is a lot of good advice above that I would like to echo or add to:
1. PTSD can get better. Hold onto that thought.
2. It won’t get better quickly so brace yourselves for the long haul.
3. Remember that it is not your fault.
4. Remember that it is not his fault.
5. PTSD will not just go away or get better by itself, nor can someone work through it on their own. That is how marriages break up and addictions are born. Make sure your husband agrees to get help and to stick with it.
6. You get help too. You need advice and support and people to talk to other than your husband.
7. Do not feel bad if he cannot talk to you about his experiences. This is one of those things that have to be talked through with people who have that shared experience.
Please, both of you, take care. I am sorry that his service to our country has cost him and you this price.