Determine what you can change and what you cannot change. There is no point in becoming upset about, or getting angry at, that which you cannot change.
Negative Visualization is the act of briefly and fleetingly considering the loss of anything you are currently experiencing. For example, if you are spending time with a friend, this may be the very last time you see him or her. The glass of wine you are drinking right now may be the very last glass of wine you ever have. When you look at the sky, this could be the very last time you see it.
Negative Visualization prevents us from taking for granted the world around us and the people in it, and promotes mindfulness.