The lyrics make me believe that it's about a couple having a conversation after some time apart ("Hush my love a train now well it takes me away from you"). Because of the distance and time, the girl, Marie, has someone else in her mind and as such he decides to leave.
However he leaves with a broken heart ("Tear the promise from my heart, tear my heart today") and hope that she feels the same pain ("Hang down your head for me") -- as opposed to being happy that he's leaving.
The lyrics make me believe that it's about a couple having a conversation after some time apart ("Hush my love a train now well it takes me away from you"). Because of the distance and time, the girl, Marie, has someone else in her mind and as such he decides to leave.
However he leaves with a broken heart ("Tear the promise from my heart, tear my heart today") and hope that she feels the same pain ("Hang down your head for me") -- as opposed to being happy that he's leaving.