Is a divorce considered to have taken place if one is afflicted with obsessive thoughts of divorce and swearing by it to oneself over every minor and major thing, and then hesitates and doubts whether one uttered it or not, or in the case of self-talk swearing by divorce to do something, but then was unable to do it for a reason beyond one's will?

One whose obsessive doubts have reached this stage, their divorce does not take effect. For marital عصمة (bond/inviolability) is established with certainty and does not cease except with similar certainty. The advice is to completely ignore these obsessive doubts, and to perceive them as a stratagem of Satan. Seek refuge in Allah from him, and do not enable him to distress the soul and bring sadness upon it. Indeed, ignoring him and not paying attention to him enrages Satan.