One of the most beautiful songs ever written and performed is Gerry Rafferty's "Whatever's Written in Your Heart." His voice has a plaintive beauty, singing about love and loss while acknowledging to his paramour past that she has to follow her heart, regardless. He's held aloft by a gorgeous chorus during the refrains. An understated solo instrument echoes in the background - which could be a lute, a guitar, a keyboard, I've never been able to identify it - during the instrumental bridge, which matches perfectly the loneliness of the song.
It can be found on the classic album "City to City" which also contains another best of all time song, "Baker Street."
Have a listen to "Whatever's Written in Your Heart."