Writers are prone to demon-trouble. You'll know the problem. That ugly, demonic monster which sits, gibbering on your shoulder, close to your ear. Mine says things like: 'Always knew you were useless. Of course you can't. Whatever made you think you could? The editor will hate it.' And so on. All deeply depressing stuff, and so discouraging to the creative flow. There is, however, a way of dealing with it, which I was taught when I did something called The Hoffman Process. I've adapted it a bit, to suit myself, but this is the basic idea. It helped me. Maybe it will help you.
Be alone in a closed-door room with a blank sheet of paper, some crayons and a heavy shoe. Sit on the floor. Close your eyes. Take some deep breaths. Ommmm if you like. Visualise that monster on your shoulder. Eyeball it. Really take a good look. Open your eyes, imagine ripping it off your shoulder, fling it down and DRAW IT on your sheet of paper. Doesn't matter if you can't draw. When you've finished, close your eyes again. Listen to all those terrible things it is saying. Open your eyes again. SCRIBBLE THEM ALL OVER THE MONSTER DRAWING. Then, when they are all written out in their ghastly glory, take up your heavy shoe. Start to hit the monster piece of paper. Really bash it. Shout at it. Tell it what you think. Don't hold back. No really. Don't hold back. Inform it that you are in charge, you are the boss, and that what it says are lies. Jump up and down on it. When the monster has dissolved into small pieces of scrap paper, gather them up. Now you can burn them, and as you do, say in your own words, something like, 'you'll never have power over me again. I CAN do (whatever it is you want to do), and YOU WILL NOT WIN.' If the monster returns (and sometimes it does), I find that lifting a metaphorical shoe in a threatening gesture does the job of sending it back where it came from. Think that no sane adult would do this? Trust me. It works. I've twice been in a room of 24 adults, all doing it, and thousands, maybe tens of thousands more would back me up.
If that demon on the shoulder exists, then it follows that so too do angels. Now, this is maybe getting into contentious territory. All I will say is that I have been thankful to find my own guardian angel at my other shoulder on many occasions. It is wonderful how, if I have to go into some difficult situation, summoning up this personage to walk behind me as back-up support can make me feel a whole lot stronger. The power of the imagination? Perhaps. But then imagination is one of the most powerful tools we humans possess. Without it, we would not have the strength to dream.