This girl that used to live in our neighborhood about 2 years ago killed herself also. She never gave any hints or threats (that I'm aware of). I wouldn't neccesarily consider myself as a friend of hers, but I knew her. I just remember that morning I heard sirens and everyone was saying that she had killed herself. She had hung herself in her own room.
After that the family had a lot of trouble, they tried selling the house and moving out of there but no one wanted to buy it. Soon the kitchen caught on fire, and everything in it was ruined. (The house still has not been sold)
Somtimes now if you walk by their house the attic light is on, and then other times it's not. One time even I remember the girl's light in her room being on.
It's pretty weird going back there... me and my friend where even stupid enough to get high in their backyard once. (I was having some pretty scary hallucinations).
Ahem.. anyways, back to subject.. I haven't really heard of anyone giving hints and threatning to commit suicide then actually throught with it, atleast not around here. But still, you shouldn't take your friends lightly when they talk about killing themselves.