You cut me down a tree
And brought it back to me
And that's what made me see
Where I was going wrong
You put me on a shelf
And kept me for yourself
I can only blame myself
You can only blame me
And I could write a song
A hundred miles long
Well that's where I belong
And you belong with me
And I could write it down
And spread it all around
Get lost and then get found
Or swallowed in the sea
You put me on a line
And hung me out to dry
And darling, that's when I
Decided to go to sea
You cut me down to size
And opened up my eyes
Made me realize
What I could not see [ Lyrics from: http://www.lyricsmode.com/lyrics/c/coldplay/swallowed_in_the_sea.html ]
And I could write a book
The one they'll say that shook
The world and then it took
It took it back from me
And I could write it down
And spread it all around
Get lost and then get found
And you'll come back to me
Not swallowed in the sea
And I could write a song
A hundred miles long
Well that's where I belong
And you belong with me
The streets you're walking on
A thousand houses long
Well, that's where I belong
And you belong with me
Oh, what good is it to live
With nothing left to give
Forget, but not forgive
Not loving all you see
All the streets you're walking on
A thousand houses long
Well, that's where I belong
And you belong with me
Not swallowed in the sea
You belong with me
Not swallowed in the sea
Yeah, you belong with me
Not swallowed in the sea
I think that "the sea" means the badness in the world and that she was getting corrupted and doing wrong things to him. "put me on line/ hung me out 2 dry". He leaves her but then he sees that it isnt her fault and that she needs help, like the rest of ppl. So hes gonna pull her out of the sea and help her.
He is saying that this girl showed him the meaning in his life... And they belong together. By "not swallowed in the sea", he might mean that literally she drowned, but i think he's just saying that she lost herself.