McGrath:

"Lili Marleen" may indeed have been named after two women, but within the song she is singular in German as well as in English: Mit dir, Lili Marleen, etc.

The song well deserves mention in this thread, however, in that, even with my small knowledge of German, I can see that the original is a far better poem than either of the English translations I have heard. Technically it is superior in that the first and third lines of each stanza rhyme, as well as the second and fourth. And it gives us images rather than gush: Our two shadows looked like one; anyone could see right away how much we liked each other.