All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
Having mere whispers about divorce does not lead to divorce; for more benefit, please refer to Fatwa 118574.
Besides, divorce by just moving the tongue without the person himself being able to hear his voice does not lead to divorce according to the view of the majority of the jurists .
As regards when a person doubts in principle whether or not he uttered the word divorce, then in principle, he did not, and so, his divorce does not take place. Thus, the certainty of the continuation (the validity) of the bond of marriage is not terminated by doubt about divorce.
For more benefit on doubts about divorce, please refer to Fatwas 82760 and 164315.
On the other hand, it appears that you are suffering from whispers and the divorce of a person who suffers from whispers does not take place even if he utters the word divorce in a way he could hear it himself, as he is considered an insane person who is driven to divorce unwillingly. For more benefit on the divorce of a person who suffers from whispers, please refer to Fatwa 119544.
Finally, it should be noted that the best way of treating whispers is to repel them and seek refuge in Allaah The Almighty from Satan and remember Allaah The Almighty as much as possible. For more benefit, please refer to Fatwa 90425.
Allaah Knows best.