Contradictions in time-travel and welfare optimization in sequential time periods

Editor’s Note: The idea that we live in a multiverse made up of infinite parallel universes, also called “alternate dimensions”, or “alternate timelines,” has been defended by various prominent physicists. In one of such hypothetical universes, the following conjecture may be taking place, and reflecting upon it may be utility-generating for scholars in various timelines:
Setting: unknown

The individual had the task of logging in extensive detail every decision taken that was later regretted to the degree that the individual considers it justifies traveling back in time to correct it, despite the uncertainty of how it will affect the chain of events. The log was kept throughout the individual’s life.

When the individual’s life was close to culmination, a time-machine was provided. The individual reasoned the essence of any individual was the result of the ongoing timeline’s chain of events. Changing the chain of events through time-travel would in essence annihilate the individual, and would be akin to suicide. The individual did not use the time-machine and died after successfully maximizing sum-of-life-utility.