I don't think divided we fall is about our state after we have fallen, or about how we fall. I think it's about why we fall, and about our state before the fall.
This aphorism, United we stand, divided we fall, shows an admirable parallel structure. Understanding the first half helps us understand the second half, and vice versa.
Now, I see there's a work of art out there that takes only the second half as its title, but I don't advise interpreting the second half independently of the first. The two halves support each other and stand together. Separate the two halves, and the structure falls down.
I paraphrase as follows:
*If we stick together we will stand like a sturdy house or fortress; but if we split into two groups then we will fall down into a ruin. *
You can look it up here.