That's a
very good question.
In a way, I think at the back of his mind, Dumbledore might have blamed himself. But ultimately it is still down to Tom Riddle's decision. He was the one who was hell bent on pursuing dark magic. He wanted to split his soul so that he can live forever. He wanted more power than he could ever have. Voldemort may have been influenced by Dumbledore somehow but all his actions is still his doing and there's no one else to blame but himself.