My first thought was of the symbol for Erzulie-The Tragic Mistress, Goddess of Love in the Voudoun religion. In it's original form, the icon (or vever in Voudon) is seen as variations on the motif of a heart pierced by a knife.
I have taken the artistic liberty of adding a traintrack piercing the heart as well. I feel it is in keeping with the original intent of the symbolic representation of the "wounding by love" and connects the icon with the motif of loneliness as represented by the traintracks and the latenight wail of the trainsounds receeding in the distance that weave their way throughout the series.
For those unfamiliar with Erzulie and what she represents, the following paragraphs are excerpts from "Divine Horsemen: The Voodoo Gods of Haiti" by Maya Deren. Dell Publishing Co., Inc. 1970.
"...Voudoun has given woman, in the figure of Erzulie, exclusive title to that which distinguishes humans from all other life forms: their capacity to conceive beyond reality, to desire beyond adequacy, to create beyond need. In Erzulie, Voudoun salutes woman as the divinity of the dream, the Goddess of Love, the muse of beauty. It has denied her emphasis as mother of life and of men in order to regard her (like Mary, with whom Erzulie is identified) as mother of man's myth of life--its meaning.
"It is as if below the gaiety a pool had been lying, silently swelling, since the very first moment; and now its dark despair surfaces and engulfs her beyond succor...The wound of Erzulie is perpetual: she is the dream impaled eternally upon the cosmic cross-roads where the world of men and the world of divinity meet, and it is through her pierced heart that 'man ascends and the gods descend'."