I love this music piece. In this song , a story about a 'couple' , they are alive , they love each other while they lie to each other, which means 'they' live in the same body. One is the specktre, the other is him/herself. Nice song:)

Song lyrics are often left open to the listener's interpretation, allowing us to attach our own meaning. That said, pop songs are not usually that deep in meaning! Here, I think the idea is that lying is a natural thing for humans to do, as natural as living or loving. It's just another fact of life. That's why it has been placed beside these other two ideas. Hope this helps!

I've not read the lyrics but the line you posted has three short facts. I would give the words their ordinary dictionary meanings unless there is other context which would makes their literal meanings sound strange. Another point is that pop lyrics are not always meaningful or well-written.