疲惫的

Frazzle \Fraz"zle\, n.
1. The act or result of frazzling; the condition or quality
of being frazzled; the tag end; a frayed-out end. [Prov.
Eng. & U. S.]
[Webster 1913 Suppl. +PJC]

My fingers are all scratched to frazzles. --Kipling.
[Webster 1913 Suppl.]

2. a state of extreme exhaustion; -- often used in the phrase

{worn to a frazzle}. [WordNet sense 1]
[WordNet 1.5]

Gordon had sent word to Lee that he ``had fought his
corps to a frazzle.'' --Nicolay &
Hay (Life of
Lincoln).
[Webster 1913 Suppl.]