"Sundown" (Gordon Lightfoot)

"Sundown" (1974) by Canadian singer-songwriter Gordon Lightfoot was a song that made frequent appearances on our home turntable.  As a kid, I just enjoyed the song's acoustic groove, which was surprisingly funky for a tune that got significant airplay on "easy listening" radio back in the day.  As usual, I didn't pay much attention to the somewhat mature lyrics.
It wasn't until years later that I really listened to what Lightfoot was singing about: a carousing, unfaithful lover.  Lines like I can see her lyin' back in her satin dress / In a room where ya do what ya don't confess simultaneously leave nothing and everything to the imagination.  (The lyrics are quite the work of literary prowess.)
I also discovered recently that the song is semi-autobiographical.  Lightfoot had been living with a woman named Cathy Smith, a background singer and groupie-extraordinaire who had pretty much been servicing The Band for years before taking up with Lightfoot in the early 70s.  (Years later, she'd infamously give actor John Belushi his fatal dose of heroin and coke in a Hollywood hotel room.)  
Anyway, you might say their relationship was less than idyllic.  One afternoon as Lightfoot was hard at work on music and lyrics, Smith got bored and decided to go out partying with friends, leaving his worried mind to conjure all sorts of scenarios of infidelity as he watched the sunset.
So "Sundown" is the uneasy thoughts of a jealous lover, who comes just short of acknowledging that his relationship with this woman is completely unhealthy.