This is not great advice for a long term solution...but for a couple of days or so it might help...I slept during the day, and went to bed really late at night, like 4 or 5 in the morning. I stayed up watching tv,cooking, chilling,it was quite fun. Then had two good sleeps in the day.for some reason, day time sleeps didn't have all the nightmares.
After three days of that, I gradually went to bed earlier, the nightmares were much better.
I think that, because I had been sleeping and not having nightmares, I didn't anticipate them, do they didn't happen iykwim.