Broken bones never quite heal all the way, they're never quite as perfect as they once were.
We are like that, in a way.
We are strong until we snap, until we're just not.
You broke my heart that September night and ever since then, my heart has tried to mend itself, but like my arm I'll never be quite strong enough again.
They say broken bones break easier the second time around, I think that's true for me too.