i give up!!!

It was a week ago that i happend to attend my friend's funeral.i went to his house to take a last look of my friend.i could see his mother sitting motionless.she was not crying but i could see the unbearable pain she was going through.she was totally blank....may be she has not still accepted her  loss.a tear was rolling down her cheek in between and she was not wiping it away.on the other side i could see his dad sitting near his only son's cold and dead body. his dad's eyes too filled with tears and pain everytime he took a glance of his son.the fishy fact is that no one could make out why he killed himself.no one knows why he finished his life with that one bottle of poison.every one thought that his life wa happy and normal or was he just pretending like that????what heart breaking incident would have happend in his life which made him to kill himself???was he betrayed???or was it something else???? whatever it is his dad and mom lost their only son,we all lost a good friend and a nice companion.how could he do this when we all are around him??? i still feel bad and guilty that when i was there as his friend why did he do this?he could have atleast told me whatever it is.if i couldnt help him out,i could have atleast stopped him from suicide.i'm not a good friend.i regret for this big loss.