Actually, I think this song is about a person in a relationship where the other person doesn't love him/her.
He/She thinks that if the other person could do it, they'd wish him/her away ("What if you could wish me away/ What if you spoke those words today), and how, if he/she were gone, the other person wouldn't miss them ("I wonder if you'd miss me when I'm gone)
Another line that has me think this is ("What if I felt like I belond").
So yeah, I think this is about someone who is finally accepting the fact that the person they are with doesn't really love him/her.
Actually, I think this song is about a person in a relationship where the other person doesn't love him/her. He/She thinks that if the other person could do it, they'd wish him/her away ("What if you could wish me away/ What if you spoke those words today), and how, if he/she were gone, the other person wouldn't miss them ("I wonder if you'd miss me when I'm gone) Another line that has me think this is ("What if I felt like I belond").
So yeah, I think this is about someone who is finally accepting the fact that the person they are with doesn't really love him/her.