The point of going back to the Citadel, for Furiosa and Max anyway, was never about surviving or succeeding. Neither of them actually believed that they would make it.
The point, for them, was the run itself. Because it was the attempt to succeed that would redeem them.
There is no safe haven in which to seek refuge, no hidden Eden to which you can return. The utopia of your youth is gone, and it doesn’t matter whether it was destroyed or it never really existed beyond your idealizing memories. You cannot ride away into the sunset and find a magical land of escape, safely separated from your old, ruined land by an ocean (of salt).
You must turn around, face the reality of your broken world, and fix it. Or die trying. Only this can save you.