The song is set in two different times. The past and the present. The old man and the young teen are the guy.
The young guy and girl were a couple and she drowned in the river where they used to meet up all the time. It was "their" spot. Anyways, the teen boy goes insane cause he was in love with her and he ends up getting the trouble with the law because he can't handle the pain of losing her. When he's in jail he keeps hearing her voice in his head and it keeps getting louder and louder. So, he decides to break out of jail and follow her voice. The voice brings him to the forest where he's chased by the police. He keeps trying to figure out where she's leading him too and he's getting frustrated and confused. That's why he's running around the woods. Then, his girlfriends ghost shows him his future if he continues with the life he's living. (This is where the old man comes in.) So, the girlfriend is trying to get him to forget about her so he can go back to living a good life. But then something strange happens and he runs into his future self in that hotel room and they both stop and look at each other.
I believe this is some future-past dimension that was connected so they could find each other and maybe that means that he can go back and somehow save his girlfriend.