Whenever you're writing a book or creating a movie or a game, your first task is to get the reader/audience/player to suspend disbelief, to buy into the logic and boundaries of your world, even though those boundaries might include things like dragons and magic. To do that, you need long threads - of history and culture.
Writing can be a tough gig. Whenever you do something in which you put yourself out there - if that becomes the focus of your life, you miss the point of living. You've really got to get the grounding of family and the things that are important in your life and make that your focus.
Writers always have confidence issues - it comes with the territory. We never know where we fit in, or what the actual value of our work might be. So we hit lulls, or slogs. Throw in the idea that many creative people are somewhat manic-depressive, and it can get pretty dark at times.