Does divorce take effect upon saying "I never said to her: You are divorced" in the context of self-talk to relieve oneself from the obsessive thoughts of divorce, while not recalling any movement of the tongue or emission of sound?

Divorce does not occur unless there is an explicit intention to utter it, either clearly or by insinuation, coupled with the intention. What happened has no consequence due to the absence of intention or utterance. One must turn away from whisperings (waswas) and ignore them.