New exposure

I recently started dating this guy who was in the army for about 10 yrs and has been contracting for the last 3 yrs. He has a Silver Star and one of his buds from his unit has a Medal of Honor. So I know they have gone through a lot of shit. I know also that he does have PTSD and he does tell me a lot of stories from his past deployments. My dad just got out after 25+ yrs with the Army and has a bronze star. So understand a lot of the military lifestyle and I know that is one of the reasons he and his veteran friends like me, I don't treat them differently or anything like that. I have dated military personnel before but never someone with his experience. In general he has his PTSD under control. I have always thought about what would I do if I was in a relationship with someone with it and how I would support them. But obviously thinking about it is very different then actually having to deal with it. Do any of your S/O have PTDS or something similar? If so what do/did you do to help when there is an episode?