Welcome to DV!

I think you got great replied, but I recommend you to start working on lucid dreaming. We have great tutorials to help you out.

When you are able to turn lucid (being a recurring nightmare, it will be easy) try to dream this nightmare again. Once you see the guy, you will turn lucid and ask him, "Who are you?", "What do you represent." He will explain what will go one, you will earn an achievement from this and you will not have the same nightmare again.

Please, drop me an MP if you like to talk!