why would you want to invent unhappiness? if you invented it yourself don't you think that was a strange thing to invent? does it have some reason or purpose? have you ever thought about it? why do we have any negative feelings or emotions?
once we experience unhappiness our tendency is to find something or someone to blame we also tend to have a negative view of ourself at these times "that would happen to me!", "typical!", "Murphy's law!" this works well for dna so we attend to things in the world or ourselves which might foster dna survival eg getting a fine for texting when driving: we feel bad about the fine, we feel bad about our own stupidity, and we might then adjust our behaviour, by no more texting while driving, which then promotes dna survival, since we then have less chance of being killed in a car crash but we never or rarely consider that the whole setup of emotions is running independent of us and is only providing us with unhappiness as a stick to hit us with to change our behaviour and force us helping dna to survive