Most of your thinking is useless.  That’s just a fact for 99 percent of us (I’m leaving out Eckhart Tolle, the no-thinking rock star).  The mind, as we recently discovered, is a Monkey (see the You Have A Monkey post:

The unchecked mind is constantly churning out useless tidbits of information that are usually fear based. Have you ever noticed that when a fearful thought starts, it sounds like a train starting its engines—  “Oh, my rent is due.”  Then it picks up slowly—  “Rent comes so fast.  I’ll never get ahead.”  Then it leaves the station— “What am I going to do when I get older?  How will I ever have enough for retirement?”   Its really moving now— “What if I become homeless?  Who will take care of me?  I can’t survive if I’m homeless!”  Now it’s barreling down the tracks—   “This country doesn’t care about me.  Nobody really cares about me!”  That train is really moving and it’s about to crash into a full on panic attack or debilitating depression.  You may even be anxious right now after having read this fictitious dialogue!

But what if you stopped that train the minute you noticed it starting the engines?  What if right after you said to yourself, “Rent comes so fast.  I’ll never get ahead”, you answered yourself with, “Is this useful?”  or, “Is that true?”  These might be considered questions from the “witnessing mind” referred to in mindfulness teachings.  When you find out the anxious thoughts are not useful, or that actually you have gotten ahead in life from when you were in high school or last year, you stop the "thinking train", set a new destination for it, and free up your energy.  Your train’s new journey might be, “What business can I start to make more money?” or, “How can I buy a place and stop paying rent?” or “Isn’t it great that I always have the money for rent?”, or “Is it time to ask for a raise?”   You give the mind train a new assignment, change your destination, and free up energy for action

The fear based train’s “actions” would probably be to “circle the drain” into panic, fear and depression. It’s destination would likely be to keep yourself stagnated, get a drink, or see if Oprah has a new show on. 

Maybe you can start questioning your mind, see if what it is thinking about is useful, and set yourself a new destination.  This is the essence of Cognitive Behavioral Therapy (CBT)— looking at the unexamined thoughts and behaviors that have been conditioned by the past, changing the thoughts if they are self-destructive, and changing the corresponding behaviors.  Yes, this can seem like a lot of work, but have you ever considered the mountains of work involved in letting unexamined thought trains leave the station, go barreling a hundred miles an hour, and crash your life?

Below the "Mental Health Matters" dude shares his experience with stopping the train: