life isn't "half over" it's already on the precipice of being over by the time you're 40. you got 30 - 40 which is your last bastion of "good years" that you can cope with.  40 - 50 you are objectively old.  50 - 60 the final years of what remains of your health 70+ it's over. so at 40 you essentially only have 20 years left and the rest is just cope.
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