You shouldn’t be afraid to just visualize a world you fear. If that world is already actual, visualizing it won’t make it worse; and if it is not actual, visualizing it will do no harm. And remember, as you visualize, that if the scary things you’re imagining really are true—which they may not be!—then you would, indeed, want to believe it, and you should visualize that too; not believing wouldn’t help you.
