Terrible story, unfortunately not a rare enough occurrence in modern life. I lost a very close friend 28 years ago under almost identical conditions, (no one saw it coming, sudden break-up of teenaged romance), it still hurts to this day. He left a huge hole in everyone else's life.
Still, I do not agree with the hackneyed explanation of suicide being selfish in all cases. If it's a housewife with small children...maybe...but depression is a powerful mental illness that removes all rational thought and logic when it's in full-swing. When someone is suicidal, they might be fully aware of the carnage they will leave behind but in such unbearable pain that they cannot stand it for another minute. The other really marked characteristic of depression is that it figuratively puts horse blinders on it's subject. Their focus of attention narrows so extremely that all they can see is schit and pain, it becomes impossible to see the bigger picture, ie. that things will change/they will not always feel this way/there could be happiness right around the corner in the near future/etc...
Depression lies to you and tells you that the way you feel now is never going to change and that life is simply pain and sadness. To continue living is to subject yourself to additional pain and rejection, financial failure and ruin, or other lovely human emotions. For people who have never experienced it and lack empathy see it as only a selfish act perpetuated on others.
