In broad strokes, it’s the story of a lady who has, for most of her life, used her looks to get by with travellers and railroad employees (it’s not clear just how “shady” she is, it’s possible she is a prostitue or a con-artist/hustler of some sort). However, as she ages, her looks have faded, as has the prestige of rail travel. Not only is she past her peak in terms of attractiveness, the American railroad system is decaying due to the rise of other options for travel and communication, as well as mismanagement. Now, she’s trying to get home to Kentucky, and having a hard time of it.
If you have a specific part that you’re curious about, post it, but be careful, as the mods don’t take kindly to postings of whole songs.