What is the song who by Bruno mars talking about?

"Who" by Bruno Mars is about unrequited love. The song explores the frustration and confusion of loving someone who does not return your feelings. Mars reflects on the sacrifices he has made for the person and expresses his disappointment at the lack of reciprocity. Throughout the song, he struggles to understand why he loves someone who doesn't seem to appreciate or care for him.

Some notable lyrical quotes that convey the unrequited love theme:

* "Why does it hurt when I smile and she's the reason?"

* "She tells me I should look ahead with my whole life in front of me. Yeah."

* "I wonder who you gon' love now. Do it to them the way you did me? And who's gonna walk when you run low? Or call to make sure everything's right with you."

* "I wonder in fifty years or so we might still be standing strong (strong). Will those eyes light up like they would when I walked your path (your path)?"

In "Who," Bruno Mars eloquently portrays the emotions, confusion, and pain of unrequited love, which resonate with many listeners who have experienced a similar sense of longing and unfulfillment in their relationships.