The global spread of the COVID-19 pandemic has increased the number of frontline medical staff complaining of problems such as anxiety, depression, and insomnia, thereby requiring urgent psychological support. Nurses are particularly exposed to various stressors and difficult environments, witnessing patients’ pain, frustration, and death, while helping them recover. Music is known to be effective in inducing psychological stability by activating brain waves, relaxing the body, and alleviating negative reactions. This study examines how musical activities affect embitterment and psychological well-being among nurses and nursing students who suffer from various psychological difficulties. This study finds that musical activity helps nurses’ psychological stability by lowering their embitterment index and increasing their psychological well-being. Further, the greater the music listening time is, the higher is the psychological well-being, indicating the necessity of increasing the music listening time and encouraging more musical activities for the psychological stability of nurses in the future.