How can I deal with my posttraumatic stress disorder?

I second the suggestion to find a therapist who is trained in Cognitive Processing Therapy (CPT)!

I'll also add that all you describe is very common in PTSD.  Emotionally, it's an exhausting condition and can take a lot of energy from the body.  Depression is a common consequence of PTSD since many people experience functional repercussions (impacts in work, social, and familial settings).   It's not fun to feel constantly terrified.  

To search for a therapist trained in what you are dealing with, it could be helpful to specifically search for folks who specialize in treating PTSD.  You can do that through Google searches, or you can also head over to Psychology Today and Therapy Den.  Both sites are therapist directories where you can narrow down the type of therapist you are looking for, as well as other factors like insurance they accept and location.

You are on the right track coming here so keep up the search!