Depression probably exists because our ancestors who killed themselves were probably more likely to reproduce.

Right so your answer to me making an assumption is to come at me with aggression? Why not talk to me about the apparent evolutionary pros of depression if that’s your field of study? That’s normally what I do when I find someone who has a misconception about the science of my field.

No you don't.

Not true. When in a depressive state a person is less likely to have the resources to have communicate well, be productive or have sex. Most species who reach a depressive spell sleep most of the time. This often leads to them being killed off by predators, exposure or starvation. None of the papers I have read have ever said that a depressive period leads to higher reproductive success.