The one to whom she's singing, and the one to whom she refers as "he". In the verses of the song, she sings in the second person about being in love with someone, then switches to the third person without making it clear that she's singing about the same guy. This must mean that she's actually singing about two different people, and is in a Triang Relation with them. It's possible this is a Type 10 Relation ("He's all that I wanted, he's all that I needed, he's all that I have"), but the lyrics of the song imply that she has a relationship with both of them ("But since I've been your girl, I'm getting stronger day by day"), meaning it's a Type 7 one.