I've had my share of nightmares certainly, but they've never been recurring
ones. I'm not a psychologist or psychiatrist.
By all means see a professional if it's causing a major disruption.
Still: chronic nightmares -- by definition, being frequently occurring dreams
unpleasant enough in some way or other to actually wake you up, seem to be a
surprisingly common problem, the prevalence of people reporting experiencing
them at one time or other being as high as 5% to 8% in the general
population. They seem to become less frequent with advancing age, so that's hopeful at least.
These days psychologists/psychiatrists seem to think that a simple
cognitive-behavioural technique called imagery rehearsal helps. There are no
large randomized controlled studies proving it, but there's an accumulating
body of smaller and uncontrolled studies that are suggestive.
The basic idea is that you record the nightmare in as much detail as
possible. Write it out fully, no matter how terrifying. When you're finished,
you change the ending of the written down dream imagery / story, preferably
into something positive and peaceful. Then you mentally rehearse the new
imagery every night, as soon as possible to the time you go to sleep. You do
this on an ongoing basis until hopefully the dream stops. If there's more than
one dream, you tackle them one at a time. There's a reasonable description of
the trick here:
http://www.guidetopsychology.com/dreams.htm
Seems as if, at least, this method couldn't hurt.
A nice recent review article about nightmares and their treatment is
referenced here:
http://www.ncbi.nlm.nih.gov/entrez/...tool=iconabstr&query_hl=8&itool=pubmed_docsum
You can at least read the abstract, and a simple search will turn up a lot
more interesting articles.
Experiencing sleep paralysis is pretty common too, I used to have this
sometimes. It's scary as hell if you don't know what it is, and understand
that it will go away pretty quickly. Many people who report being possessed or
held down by demons at night are likely describing sleep paralysis. It's not
hard to understand how they could think that, if they had never heard of the
syndrome.