Driven to distraction; colossally frustrated; a combination of being worn out from -- and pissed off by -- the offending person or circumstances.
Root: Yiddish?
Even though she provided tangible proof, the final decision was not in her favor; she was entirely fatootsed by the entire episode, and vowed to put it -- and all its associated michegaas -- behind her and move on.
The fatoota is all. It is the best..
It can be whatever you want it to be..
(i.e. any body part, any verb, adjective, pronoun, noun, person, place, thing, idea, the FUTURE!!!!!!!)