That's generally the problem with untreated PTSD (insert not all sufferers, etc)- the supporter has to be able to be completely independent emotionally, and have their own support system that largely doesn't include the sufferer. My sufferer could not handle my health issues, either, even though I am under a doctor's care, and did not expect him to do anything about them - anything I told him was at his request because he wanted to know. And emotional? Fuhggetaboutit. He called me abusive for having stressful days at work, and not be able to completely leave the stress at the door (IE, being not quite as happy as normal while at home because work was stressing me? That was abusive according to him).
I didn't realize how unhealthy and codependent I was, constantly walking on eggshells and swallowing my own stuff to avoid adding to his stress, this was until we separated.