The Chainsmokers - Honest Lyrics Meaning

He is in love with two girls (u r not the only kne on mind). He thinks about this every night and doesn't share this feeling because he can't choose one from them. He is supposed to call in morning and justify this but he Doesn't know what to say and he is just listening radio at 5 am. It's 6 am and now it's too late and he is too far from her.