You and Alec were childhood friends, but when you were older, Alec moved away from you. He didn't want to go because he loved you, but he didn't want to hurt you, because he was always surrounded by fans and the pressure of fame

At one of your shows, Alec looks at you and sings

I kissed the scars on your skin I still think you're beautiful And I never wanted to lose my best friend

He looks back at the fans while playing his guitar. you knew that was a hint.