in once もっと見る with feeling where duse buffy say she is liveing

"I live in Hell, 'cause I was expelled from Heaven."

That the line to which you're referring? She says it in "Give Me Something to Sing About."

I don't she does, but I think this is maybe what あなた mean-
Life's not a song.
Life isn't bliss, life is just this, it's living.
You'll get along,
The pain that あなた feel, あなた only can heal によって living.
あなた have to go on living.
So one of us is living.
Spike 歌う to Buffy
it's towards the end it's apart of the song Something to Sing About
I hope this was helpful, sorry if it isn't what あなた were thinking of! :)