Lyric discussion by DeathRacer 

Cover art for Cosmic Love lyrics by Florence + the Machine

I also believe this song is about unrequited love that is, returned in the end, but I don't think love is being potrayed in a positive manner. Darkness symbolizes loss, sadness, confusion, ignorance, etc., none of which are ideal states of being. The fact that all light providing entities are blown out enhances this fact. In the end when they are both in the darkness, I see it as they are both so consumed and infatuated with each other that they lose touch with the life and light around them. They love in desperation and obsession. Love, in this case, seems like an unhealthy need, one that steals them away from other positives in their life. But a song/poem can be read in a myriad of ways. This song like most others can have many meanings.