I honestly think this song truly means that, they love each other.
But they are having downfalls.
They have so much in store for their future, but if they don't keep believing in it, he thinks it will never happen; and he dosen't wan tot give up on such an amazing relationship.
He feels that most of the trouble, and problems were his fault, & he's praying to change everything and make everything go back to normal.
He can't help but to fall for her, because she's everything he wants & needsm and he doesn't want to loose that.
He talks about how the world has so much to ffer, and that if they overcome this trouble and problem, they will make it through.
-mya.