My memorable song is IU's Ending Scene. It is in Korean so sorry for all non-Korean Anker users. This came out when I broke up with my girlfriend of 3 years. I am still getting over her but whenever I hear this song, it reminds me how desperately I miss her.
I think this event is really meaningful.. song really does place people back to moments in the past, happy or sad. Probably that's why we love music.