The speaker is comparing themselves to another girl, and they feel they come up short. She is sweeter, bolder, more fun to talk to, and she shows she cares. She also fits neatly into the life of the person being addressed: she is friends with their best friends, likes the same genres, and knows the songs they love. The speaker, by contrast, says they have none of these qualities.
The repeated "way better" gives the poem a flat, almost defeated tone, like someone listing their own flaws because they've already given up. The casual, slightly broken phrasing makes it feel like a private confession rather than a polished speech. Then the last line turns things around. The speaker has listened to every song the other person likes. It's a small, quiet gesture, but it shows real effort and love. The mood is wistful and tender, with a hint of hope that being sincere might count for something.