My mind gets to wandering, and I become troubled.
Isn't this exactly what happens, especially in the middle of the night? Many tiny fears jump into your head and you're unable to sleep. Those tiny thoughts manifest into your greatest fears. You start to worry about your children, your finances, your parents, war, the world, any fear you have ever contemplated. It doesn't matter, what the fear is, when it is the middle of the night these issues seem totally insurmountable.
Your rational mind may know they are just thoughts, not real, but that doesn't calm you down, or ease your mind. Like a frightened child responding to the 'boogeyman', the fear is so intense that the idea alone is enough to scare you. Your stomach is churning, and the thoughts just keep on coming, informing you of what could happen.
Anything can happen and that's what scares you... but you are projecting into the future. In the here and now, there is a person, safely tucked in bed, awake. The thoughts have come into your head, but where do they fit into the reality of where you are in this moment? You are safe, none of this stuff is actually happening, and yet you are stressed and anxious, over what? A random thought, a misplaced notion, nothing reasonable or rational, just crap.
"Change your thoughts and you change your world." Norman Vincent Peale
To quote Byron Katie: "do not believe your stressful thoughts" and in my words....don't listen to them, do invite them in, pay them no mind; however you want to say it. Drop them like they are hot.
"The only time we suffer is when we believe a thought that argues with what is. When the mind is perfectly clear, what is is what we want."