With Mindfulness practice, you can learn not to let negative emotions consume you. Anger, fear, sadness, greed, jealousy, envy, anxiety, loneliness are just a few of the many negative emotions an individual has in their lifetime. We can not stop from feeling these emotions, but we can learn to control how much they affect us. You will get sad, annoyed, upset etc., but it is about how much you let those emotions build to where it causes distress and misery.
Whenever you feel any of these emotions. Take a step back, sit with the emotion, accept what you are feeling, and remember the emotions will eventually fade. The first step is to become aware of the emotions you are feeling. Awareness is important. After becoming aware. Identify what is upsetting you. You should try not to attach any positive, or negative emotions to the feelings. Try to look at the situation in a non judgmental way. When you are able to do that. You will be able to see the reality of the situation.
We tend to attach negative thoughts to these feelings, which creates more negativity, misery, discomfort etc,. We also react, rather that stepping back, which can lead to guilt and regret, and that creates more tension. It is all about controlling how much these emotions affect you. You may not have the power to stop these emotions from happening, but a mindful approach can help you stabilize the emotions where it doesn’t get out of hand.
Psychology of Mindfulness 