Eknath Easwaran's Commentary
Often, when a low mood is coming on, sometimes it is because the mind has started to brood upon itself. The things that formerly seemed exciting now elicit no response. In a sense, we have closed down. A friend can talk to us and we will not hear; we can go to a movie and may not even follow the plot. We are utterly absorbed in a hall of mirrors inside, in which we and everyone around us are pushed, pulled, and twisted into fantastic shapes.
There are a number of effective ways of treating these dark moods where they start, within the mind. What helps is to do what your mind is crying out not to do: be with other people, work with them, make yourself take an active interest in what they are doing and saying. This turns attention away from yourself by directing it outward. Once you are more concerned with others, your melancholy is gone; you are alive again.