There's a particular line of The Desiderata[0] that says so much in so few words:
no less than the trees and the stars; you have a right to be here.
It provides armour to me when the negative voices come. It reminds me that I am privileged to be alive at this point in time and help to remind me of the (good kind of) "holy shit" feeling I should have at that realisation.
Some holes are too deep for this to have an effect, but for the shallower ones, this has helped me escape them quicker.
You Have A Right To Be Here!