Basically, the song’s about a guy cheating on her and then having her stuck in his head due to guilt. So when she’s in the back of the car, she’s not really there, it’s all in his head, same with the bathroom scene.

As far as the bath thing goes, I think it’s suposed to represent that she feels like she’s “drowning” in the relationship then at the end when she leaves him nd sits up in the bath, it’s like she feels free again.
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