MomnLaw,

Welcome to NeuroTalk.

Has anybody done any serious neurological testing on your DIL ? Many of her behaviors can be the result of a brain injury. A drug test to rule out drugs would be good so you can get past that question. Then, it will be easier to push for a diagnosis of a physiological cause to her behaviors. A high Tesla MRI or a DTI MRI would be warranted. A 24 hour EEG might be worthwhile. She may be having seizures, absence or otherwise.

Her behavior could be a combination of an mTBI and PTSD. They tend to magnify each other.

btw, A DTI MRI is a Diffusion Tensor Imaged MRI. They are good an showing a physiological (trauma) cause to cognitive problems to rule out psychological causes. I wish I could find the MedScape article that explains this.