Those sad sad songs that make you want to cry...

Seasons in the Sun - Terry Jacks

Honey - Bobby Goldsboro

There's a lot of them, but the first one that came into my head was " A Rainy Night in Georgia."

Hearts - Marty Balin

Empty Garden - Elton John

Angie - Rolling Stones

Here today-McCartney

I Dreamed About Mama Last Night: Hank Williams (a great version is by Johnny Cash, as part of a tribute album to Hank Williams called Timeless).

Everybody Hurts by R.E.M. 

The Old Lamplighter: The Browns.