If you have a friend who starts talking about how things might be better for their family if they weren't around, or if they start to give away all the things they care about, tell someone. And let your friend know that you care and that you're not going to run away or dump them just because they're going through a bad time. And if you have a friend who's depressed and you know they have access to a gun, you really need to tell someone, because when there's a gun around, people are more likely to use it. I hope this doesn't scare you and just gives you a better sense of what to watch out for and what you might do to help. Sometimes it doesn't matter what you do and if a person is really determined to kill himself, he will.
Adolescence is a rough time.
A year later, my daughter ran into a casual acquaintance from her school. The other teen was distraught and told my daughter how she was seriously thinking of killing herself and how none of her friends seemed to take her seriously. My daughter told her that she couldn't ignore what she was hearing and that she would have to do something. And she did. She contacted the school and told them what had transpired and asked them to contact the girl's parents.