PTSD survivors, like to think that they can take care of themselves, because that is what they had to do after their trauma. What you can do is find her a PTSD therapist, and encourage her to go and talk to one, it will change her life and it will actually give her a life, like everyone else has, except she will be all straighted out

A PTSD therapist is trained to help victims release all the anger and place that trauma where it belongs so it doesn't control her, she can control it
I have been where she is now, because she is so unhappy, she doesn't see what it is doing to those around her. I retreated to my own world, I didn't need any help, I had survived 30 years with my secret and I would carry it forever, until the secret/trauma starts to bubble up, and because we have never been asked how we were feeling, we can't communicate to anyone how we really feel.
For me the trauma decided that it was time to tell, so I told my husband, and boy did that feel great, then I told my mom, and eventually I went to a PTSD therapist, who worked with me, and believe me I didn't understand half of what she was talking about, so I would say that, I don't understand and she would help me understand. I decided if I was gonna go thru all of this, I wanted my eyes WIDE open and I now have a nice life.
IF I can do it anyone can do it, it is just so freeing, you can't force her, you can find info about treatment for PTSD and the procedures that the therapists use. I have a female therapist and I that worked great for me.
I wish you luck, be patient with her, be there for her, don't smother her, support her. Have her read this message, maybe it will help her.
Hope she feels better you are a great guy to stick by her