Lyric discussion by sunnyaurora 

Cover art for Crashin' lyrics by Jack's Mannequin

I think he general idea of this song is a post-breakup. The chorus really hits home for me.

And even if your voice comes back again Maybe they'll be no one listening (even if she comes back to him he may not be there then) And even if I find the strength to stand Doesn't mean I won't go missing (If he can find the strength to not let her back in, he may very well lose all contact with her because even a little would break him down and let her back into his heart) And the world will come Crashin (it will all hit her what has happened)

i think the "crashing" is generic and changes meanign throughout the song though. Crashing is just a metaphor for life hitting you in the face. Just as it does after a break up. This is an optimistic break up song though which I really appreciate.