So someone who kills someone else due to mental illness is a vile human being that deserves a prison sentence, but someone who kills themselves due to mental illness is deserving of our sympathies and empathy.
You can't look at a rapist and say that he couldn't help it, his brain chemicals were jacked up and try as he may have, he finally succumbed to his temptations. So why are we fine to say that suicide victims couldn't help it, and that the chemical imbalance was to blame?
I know, I know, I haven't brought up Nazi Germany yet, but keep avoiding the question and I'm sure it will pop up.