I think its about a couple that always had their "i cant live without u" moments like every couple, then he got sidetracked with other things and like pushed her aside. Then they get into a big argument and she runs out and he runs after her. She runs across the street she gets hit by a car and he's put in shock. He runs to her screaming and crying over her body. The ambulance comes takes her away. He goes to the hospital and gets the news that she's dead. And he feels like part of him has died. When he returns to his apartment everything that's there reminds him of her, so where he just can't take it anymore he starts thinking about taking his own life. Then a knock at the door. He opens it and his eyes get wide with shock that its her. At the end of the song it says "Please come now I think I'm falling, I'm holding on to all I think is safe" is where he hugs her really tight hoping she wont slip away again.