For me, it's been easier having "made up" nightmares than dealing with whatever is on my plate at the moment; some part of me knows it's not real whereas when I start messing with real problems that are harder to solve or get to go away it can be frustrating and make me lose hope. But when I was 20 I faced the fact that they weren't real and decided to get rid of them (and couldn't) and that's how I got into therapy. Over the years (I'm 56 now) things shifted and changed and eventually all came out so it's "quiet" now, no untoward thoughts, daydreams, daymares :-)