If someone were presented the option to permanently undo a major aspect of their

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If someone were presented the option to permanently undo a major aspect of their own life, and "rewrite history", would it be morally wrong to do this? Consider the following scenario: a person dedicates their life to an ideal such as justice or peace or any morally sound ideal such as those. They sacrifice so much of their time, energy, life, and sanity to the fulfillment of this ideal. However, due to unforeseen circumstances their actions lead to an outcome they were unsatisfied with. Would it be wrong for this hypothetical person to change their entire life to avert this terrible fate?