What is the proper ETIQUETTE when someone is going to kill themselves?! first of all, if they do jump in front of a train, it will destroy their family's happiness and their own life WHEN YOU could have done something to stop it from happening. if the person does not want to live, then don't let him do it now, but rather when you are not around to witness his suicide, because that would probably be quite grotesque just to watch it happen..