If you actually look at the lyrics.
I'm done with this chorus, I hate it so much.
All those other girls, well they're beautiful but would they write a song for you Well you know what Taylor Swift? That could cause some problems.
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This is just a preview! And she was younger when she wrote the song.
Taylor, by the time you released the song and were promoting it you didn't even like the guy anymore because you told him about it and showed it to him.