I am the wife of a survivor and although I am not very familiar with your situation, I have found that educating myself has been one of the top things that helped me understand a bit more and as a result I began to handle my husband differently. I too didn't understand why he can't just "get over" this. I had to learn how serious PTSD is. I had to learn about the brain's response to trauma etc. and that it is in fact a (mental) health problem. They're not just some bad memories. His brain literally won't let him let go of this. Then I decided that I said "for sickness and health" after reading some posts on here. My husband doesn't have cancer, but PTSD is also a sickness. It is all very difficult for both parties but educating myself was something that made me change my tune with him.