Wikipedia says "Depression is a mental state of low mood and aversion to activity" - that's what I meant.
Mental illness is I think a different thing. Depression doesn't imply mental illness, nor does mental illness imply depression. I understand and agree that many people let mental illness come between them and whatever. It's a problem. It's just a different problem.
They didn’t have the option of neglecting their kids either; somehow it doesn’t stop them from doing so anyway.