Have you tried to write them down in something like a dream-diary? I found it helped me a lot to reduce the severity and intensity of my nightmares. Even reduced the amount of nightmares from every night to every second night. Although I would suspect that I'd get locked away instantly if someone ever read that journal.

Just a suggestion, not a do-this-do-that. Can't guarantee it helps, but when it comes to nightmares .. I really hope you'll find something that helps you someday.