Hi Amelia,
Welcome to the forum and very glad to have you here. Bob spoke with me about referencing you here, which is great that you decided to join.
I dare say that must have given you a bit off a shakeup when your husband did that with you. Its funny though, in that I am the opposite, where if something loud occurs, I go into it, and not go to ground. I guess it has something to do with the Australian military training, where it becomes instinctive to go into the danger, and not fret from it. From my experiences, the Australian military training is vastly different from the US military, most likely the difference in reponses to those situations. Some Australian soldiers do similar things to you husband, but the majority tend to have that immediate response to move into the danger and fight through it, as we are trained instinctively to do. Strange... but very much a part of how the military brain washing takes hold of you and becomes part of your life even after the military.
As for help Amelia, you will find great assistance here from other spouses who understand the spousal side to living with PTSD. Spouses are often forgotten about, and generally suffer the brunt of all PTSD, being the closest to the sufferer. Spouses need more recognition than they get IMHO.