Natasha stated in an interview that the song "is like the true love song on the album and it sort of - not an anti-love song at all - I can’t think of how to phrase it, but it's sort of the resolution of, the antithesis of romantic, heightened, superficial love, and it’s almost like a thank you letter to her lover for kind of helping her through this journey. So it’s kind of the deepest form of unconditional love - so for me it’s hard to listen to that, it’s kind of tearful."
Natasha stated in an interview that the song "is like the true love song on the album and it sort of - not an anti-love song at all - I can’t think of how to phrase it, but it's sort of the resolution of, the antithesis of romantic, heightened, superficial love, and it’s almost like a thank you letter to her lover for kind of helping her through this journey. So it’s kind of the deepest form of unconditional love - so for me it’s hard to listen to that, it’s kind of tearful."
Source: http://pilerats.com/written/get-to-know/bat-for-lashes/