I wish there was an all of the above option. IMO..Teen suicides are due to peer pressure which leads to drinking and/or drugs, low self esteem, and an unstable home-life. All of these things can lead to psychological problems making it hard for the teen to decipher between reality and disillusion.
There are usually a lot of red flags or warning signs that a person shows before they actually take their own life. If someone is suffering that much and sees death as the only solution, there is little or nothing that can be done to help them. If they don't succeed the first time, they will keep trying until they do.