It's about a friend, besides I'm not sure her mother is dead...
Salutandomi/saying me goodbye
Da quel luogo che è un luogo senza te/ i know it's a bit twisted but your translation is right, perhaps you could translate these last two lines with "from that place where you're missing"
Te ne vai da qui/ you leave this place
Con gli occhi lucidi/with watery eyes (occhi lucidi means there are tears in your eyes but you're not crying)
Che piano si colorano/that softly colour
Di bianche nuvole/ with white clouds
Ti dico CIAO/i say you : goodbye
Con quell’ultimo battito/with that last flutter
Che d’ali diventò/that became (a flutter) of wings
Dall’ultimo metrò/from the last metro
Sovrasta il vocio/overwhelms the shouting
E lascia il ricordo/and leaves the memory
"-Please tell me you're going to appeal to my humanity..."
"-Actually, I'm planning to threaten you."
"Well, if you'll excuse me, I have work to do. Evil plots don't just make themselves, you know!"