When partners begin to find fault with each other, they are in the stage of the de-escalation process?

Answer;
Turmoil stage
When partners begin to find fault with each other, they are in the turmoil stage of the de-escalation process. 

Explanation;
Turmoil stage is the stage of de-escalation that comes first in relationship demise and is characterized by increased conflict as partners find faults in each other. The definition of the relationship loses clarity, and mutual acceptance declines. Conversations are tense, difficult, and forced.

cell would not be able to produce protein, got it from google