Verse 1: She has loved this guy for awhile, but never told him. Her heart beats fast when she's around him, she has so much "colours' or the joys of living and being alive, that she wants to share with him, so many promises that she wants to make, but she's too afraid of "to fall" perhaps that he doesn't return her love, that she can't tell him. But he's standing all alone and she sees her opportunity. All her doubt goes away--she must tell him. She takes a step closer to him.
The chorus is her confession that she loves him. She's died every day waiting for him--it's painful to always see him and want to tell him how she feels, but not be able to. She keeps waiting for him to make the first move, but he won't. She tells him not to be afraid--she doesn't want to scare him away--but she's loved him for a thousand years--it feels that way to her, at least--and will continue to love him for a thousand more.
The second verse is back before she confessed, while she is still going toward him. Time stands still for a moment, a beautiful moment as she reaches him. She's going to be brave and tell him how she feels, she won't let fear or anything else take this away from her. Every breath, every hour she has spent waiting for him has come to this one moment. She takes one more step forward.
Once more, her confession.
I believe at this point he tells her that he loves her too, and she just wells up with emotion. All along she knew that she would "find" him, or that he would finally know how she felt. Time brought "heart" to her, meaning that her feelings grew and developed until she was ready to tell him. She repeats that she has loved him for a long time and will continue to love him.Every word uttered is one step closer to the happiness she has dreamed of.