Die Geschichte ist lang, wie die eigene Familie Krishnas selbst zerstört hat, weil es keine waren, die sie besiegen konnte, so wurde alle von der Mutter der Kauravas "verflucht", weil so es Krishna wollte.
"After the death of 
Duryodhana in Mahabharata, Krishna received the curse of Gandhari. She bewailed the death of her son and of friend
 and foe; then 
recognizing Hari  (Krishna) as the Prime Mover, the 
One behind All, she cursed him for letting such things befall.
 This was her curse: that after 36 years Krishna should perish alone miserably 
and his people, the Vrishnis, should be destroyed.
These things in due time came to pass. A "madness" seized the people of Dwaraka so that they fell upon one another and were slain,
 together 
with all sons and grandsons of Krishna.
Only the women and Krishna and Balarama remained alive. Then 
Balarama went to the forest, and Krishna first sent a messenger to the
 Kuru city, to place the city and women of Dwaraka under the 
Pandavas protection, and then took leave of his father; afterward he
himself sought the forest, where Balarama awaited him. Krishna discovered his brother seated under a mighty tree on the edge of the forest; he sat like a yogi, and behold, there c
ame forth from his mouth a mighty snake, the thousand headed 
naga, 
Ananta, and glided away to ocean. Ocean himself and the sacred rivers and many divine nagas came to meet him.
Thus 
Krishna beheld his brother depart from human world, and he wandered alone in forest. He thought of Gandhari's curse and
all that had befallen, and he knew that the time had come for his own departure. He restrained his senses in yoga and laid himself down.
Then there came a hunter that way and thought him a deer, and loosed 
a shaft and pierced his foot; but when he came close the hunter
beheld a man wrapped in yellow robes practicing 
yoga. Thinking himself an offender, 
he touched his feet. Then Krishna rose and gave him comfort, and himself ascended to Heaven.The hunter is said to be rebirth of Vaali from Ramayana who was killed by
Rama by hiding behind a tree and was therefore given the opportunity to avenge in similar fashion by Rama (in the form of Krishna).
Gruß
anadi