Oh so sorry you had such a nightmare hugs...
Have you had any close encounters where you have felt threatened?
Also maybe its something from the past that's resurfacing, maybe triggered by feeling isolated and who you are?
What I do when I have less than wonderful dreams and end up awake half the night, is to think of all those positive things in life, or a dream of life in the future.
Try and get a good nights sleep tonight xxx
Hugs
Katy