Having survived the Vietnam War in 1969/1970 and heavily traumatised, I know and have experience of what your husband is going through.
If I may offer some (unsolicited) advice, just be there for him, get help if you can and connect him to people who have overcome PTSD.
Don't beat yourself up on his situation, it is not your fault!
Keep doing your damnedest, showing love and compassionHi @rachinata, I hear you!!