(((((((((((((((((Rose3)))))))))))))))))))
I know how unnerving those nightmares can be. I'm sorry you are going through them.
Many times the nightmares and dreams are extensions of what our subconscious is thinking about. They may be very fractured and hard to understand.
I'm not sure how to stop them, but possibly when you go to bed at night, listening to some calming music, or thinking about something happy that feels good just before you go to sleep might help. It's worth a try I think

Remind yourself when you awaken from them that they are only bad dreams, breathe deeply in and out, try again of thinking some pleasant thoughts while you drift back to sleep.
I wish you well and hope they go away soon!
Hugssss
J