It means that they were already lover's before and had become complete strangers to each other when they parted ways. One singing the song expresses her recalling the times that never happened because the past is completely gone and no one would have to know it. It's like a secret relationship that she had with the former lover that only her and that person could recall.
It means that they were already lover's before and had become complete strangers to each other when they parted ways. One singing the song expresses her recalling the times that never happened because the past is completely gone and no one would have to know it. It's like a secret relationship that she had with the former lover that only her and that person could recall.