She had a recurring 'nightmare' [=she had the same bad dream many times] about losing her job.
Losing a child is every parent's 'worst nightmare'. [=the thing every parent fears most]
Mommy, I had a really scary 'nightmare'.
(..) what we have to do, but you're too scared to go through with it. I'm gonna burn this fucking place down. and I'm gonna end this nightmare. Why don't you just run away? Go hide beneath some rock somewhere. You know, You're great at that. Oh, shit! (..)2013 Evil Dead