In my opinion, this song is about a girl who gave her all to a guy and loved him with all her heart when he never really felt the same. He never really took what they had seriously, he just used her and "took the very best of her" when it was convenient, and then left her to pick up the pieces. But she always went back to him, because he "had a way of coming easily" to her. But as she is writing this song, she realizes that he never really cared about her and just how cold he really was all along, even though she wanted to believe with all her heart he wasn't. This is a reflection of the relationship, a sort of coming to terms for her.
In my opinion, this song is about a girl who gave her all to a guy and loved him with all her heart when he never really felt the same. He never really took what they had seriously, he just used her and "took the very best of her" when it was convenient, and then left her to pick up the pieces. But she always went back to him, because he "had a way of coming easily" to her. But as she is writing this song, she realizes that he never really cared about her and just how cold he really was all along, even though she wanted to believe with all her heart he wasn't. This is a reflection of the relationship, a sort of coming to terms for her.