Blame evolution. We have evolved to stay safe. That is a reason why we constantly relive our mistakes of the past and why we have bad dreams hammering this worry and fears into our brains. Animals that worry too much and so take greater care still live long enough to procreate and pass along thee worry and bad dream genes. Even if they don’t live the happiest of lives. Evolution does not work to make us happy, only to procreate.
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