Same, It's this completely irrational fear, I can't seem to get rid of, Even though I know rationally that once your brain ceases to function you are in capable of ever being conscious, I still have the fear that somehow, someway, that consciousness will be thrust upon me once again, Resulting in a never ending cycle of needless suffering induced life.
I think my fear is sort of simply just that it might reveal to me a world in which there is no way to escape, making me face a messed up reality in which their is no way of ending the suffering that every conscious being experiences. More selfishly that I Would never be able to escape.
It's like one of those anxiety inducing ideas that your mind come up with when you are just about to fall asleep, except it never seems to leave.