No matter how it’s framed, seeing the traumatized person as not resilient implies that there’s something they could’ve done. That’s what they already think and the notion of resiliency reinforces that belief, which I think is false. If they could’ve, they would’ve. The essence of the post-traumatic illness itself is an attempt to "prevent the past" – eg become more resilient going forward through hypervigilance and other maladaptive mechanisms. Traumatic symptoms are often perceived by the afflicted as a defect, something bad about themselves. It’s hard enough to help them accept that it was something that happened "to them" rather than a weakness or something they did without throwing in un-resiliency to needlessly complicate matters.It is always the same. The doctor, when faced with problems that are hard to grab, is tempted to see it as a fault of that person (instead of an lack of knowledge) – so if that person does not get better, it is the person's fault, and the doctor is vindicated. And if the person does get better, it is as well vindication of the doctor. The doctor can't loose with "blame the patient".
(Furthermore, having experienced personally, and read many anecdotes on how our "modern" nutrition drives anxiety, I strongly suspect that nutrition might play a substantially contributing role in diseases from the psychological/psychiatric/mental/neurologic/whatever spectrum like PTSD.)