The Ghost Of You

Basically he is pondering suicide so he can be with the girl he loves because he can't forget her. Here are some more exact lyric picking apart stuff...

"I never said I'd lie and wait forever
If I died we'd be together
I can't always just forget her
But she could try"
It's him knowing that they can't be together so he's not going to wait. He is pondering if he should commit suicide to be with her, thinking that he will stop remembering her, which could be why he is calling her a ghost. He can't forget about her no matter what he does, but she could try forgetting him.

"At the end of the world
Or the last thing I see
You are
Never coming home
Never coming home
Could I
Should I"
This, to me, seems like he is thinking about suicide and that if he did it, could he be with her. Should he commit suicide knowing that he might not be with her

"And all the things that you never ever told me
And all the smiles that are ever ever
Ever"
It hurts him when he thinks of her and him together, whether they were together or not, and all the laughs and smiles that they shared.

"Get the feeling that you're never
All alone and I remember now
At the top of my lungs in my arms she dies
She dies"
Although she is dead, she isn't dead in his heart and in his memories, and when he mentions the ghost of you, it could be referring to the memories of her and when he say that "at the top of my lungs in my arms, she dies" It's the pain that she brings him when he remembers her.

"And all the wounds that are ever gonna scar me
For all the ghosts that are never gonna catch me
If I fall..
If I fall.. (Down)"
For all the memories he can't forget and all the memories that hurt him are never going to leave him. I think this is where he decided to not commit suicide. Even though he may be hurt, he will continue to live on and pick himself up. He will try to forget the past and move on.