To me this song is about hurting. To me it's saying that sometimes, you just have to hurt to move on. And sometimes you can't and you'll never be able to.
It's songs like this that make you feel something, something that's bigger than you, and felt by everyone. You feel that kind of hurt, but it's that kind of hurt that makes you smile as you cry
thererealsugarbaybee, I understand what you're saying, because that's exactly how I view this and how I feel.