Nine Inch Nails - The Fragile Lyrics Meaning

This song is about Trent.
The female is what Trent wanted to be.
He wanted someone like the protagonist to love him the way the protagonist loves this girl -
this song is what he wanted, he wanted someone to save him.

To put in a story interpretation -
The protag finally meets his soon-to-be significant other. The same one who commits suicide in "LA MER"
She is damaged. Just as the protag is.
But he isn't letting her fall apart like he is.
After all,
They're in this together now.