Lyrics from Apologize, by One Republic
'... I loved you with the fire red now it's turning blue... '
Think. A luminous flame gives an orange (or if you give a little leeway, red) flame. A non-luminous flame gives a blue flame. So if the song is trying to say that his love for his significant other has waned... then it is in fact wrong! For we all know that a blue flame burns at a higher temperature as compared to a red flame. (:
charles