Does divorce occur if an unconsummated wife does something I forbade her from, and I told her: "If this happens, then each of us goes our own way," and then she did it because her father coerced her and she forgot what I said, and do fear and forgetfulness excuse her?

Your statement to your wife, "Each of us is on a different path," is an كناية (indirect statement) of divorce. If you did not intend divorce by it, then nothing is binding upon you. However, if you did intend divorce, and your wife performed the action that the divorce was conditioned upon out of fear of harm from her father, then the nature of this harm must be considered: If it reached the level of legal compulsion (إكراه شرعي), then nothing is binding upon you. But if it was minor, then the divorce occurs. As for her performing the conditioned action forgetfully, divorce does not occur by it if she was keen on not making you break your oath.