Have you by chance tried to talk to your doctor about something that will keep nightmares with panic attacks at bay?
I remember one friend I had that had PTSD related nightmares took a certain antipsychotic that really helped her out.
I took the same one and it made me all screwed up though, it's a hit or miss apparently.
I also get some pretty crazy dreams that has me waking up in cold sweat, shaking and what not, it's no fun at all, I'm sorry you're going through this.