In Buddhism, they advise against spending time pondering "unanswerable questions." [1]
If you know a question is unanswerable, and mulling it over makes you unhappy, then it's foolish to continue thinking about it. You can just leave it be and move on with your life. I think most people eventually figure this out on their own some time in their late 20s.
[1] https://en.wikipedia.org/wiki/The_unanswered_questions#Sabba...