Experiencing a low mood or increased sadness at night is a common phenomenon often referred to as nighttime depression. The solitude and quiet surroundings of the night can intensify feelings of loneliness and isolation. People tend to be busier during the day with others around. Without these distractions there is less to concentrate on. Also being physically and emotionally tied at the end of the day lowers your resilience. making problems loom larger and more difficult to manage.