nightmares happen when i go to sleep really really really tired (like around 2-4am).. then i have to kick myself back awake and force myself to turn over—very hard to do when so tired, which is why that’s when the nightmares can come.
did you know that’s the cure to breaking away from a dream? if you don’t want to slip back into a bad dream, you must change body position signfiicantly—turn your body over. same is true for good dreams—if you wake up in the middle of a good dream and don’t want to lose it, then try to keep still—do not roll over or turn your head.
i’m sure this is documented in science somewhere.. i’ve been meaning to look it up. but through lots of personal practice, i can guarantee its truth.