Not having heard the recording in question (whatever it might have been), I can only guess at the identity of the song: but I should say that it's John and Moll, which has turned up in oral currency as Love Farewell (and other titles). Number 1301 in the Roud Folk Song Index, where only a small number of examples are listed (I haven't yet seen the new edition just out), all from England and Scotland.

You can see a London broadside example at Bodleian Library Broadside Ballads:

John and Moll

Did Dolores say where she got the song?