system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Insomnia. What's really going on biologically and psychologically and why does it happen if sleep is so necessary for survival.

My mother has crippling insomnia and it makes her hate life. Suicidal, anxiety, depression and just all round amplified negative emotions. Unsurprisingly, she had a turbulent upbringing. Also, does the body just get to a point where it just crashes from excessive sleep deprivation? If so, wouldn't sufferers of insomnia benefit from comas as they finally get... sleep?
gpt
Evolution doesn't weed out deficient or destructive behaviors. 

All evolution "cares" about is whether something gets you killed before you can pass on your genes. When nobody is left to carry on a particular gene, that trait dies out.

Evolution doesn't work to make traits *better*, it's more of a "if the trait won't kill you, it's not going to change."