Michelle Branch - Goodbye to You
I've always liked this song. This is the official video, and I also am posting a clip from Buffy. I'd already heard this song before they used in "Tabula Rasa", but it just fit perfectly with the scene and made it even more powerful. The fact that Tara left Willow was incredibly sad, and the song basically described everything Tara was feeling, too. God, I miss that show.