Here's a good link about mindfulness meditation. It has been an extremely valuable gift in my recovery. I believe it allows you to join your awareness with God's awareness. The negative thoughts just fade away.
The actual practice is extremely simple. Sit in a straight back chair, close your eyes, and focus your attention on your hand or a finger. When you notice that you have been dragged into your thoughts, gentlely bring your attention back to your hand. Watch your thoughts without judgment. Do the meditation 20 minutes a day, twice a day if you can.
You will find that this type of awareness is an unbelievable gift.