Why did Voldemort go bad?

[lesley]

No: HPFGUIDX 184123

I have never understood this, i apologize if this has been addressed 
before but why was he bad?

Ok so he was an orphan, the childrens home (from the little we saw of 
it) seemed like a nice place, at least it wasn't a bad one anyway!

I don't believe in blood will out personally and there isn't a lot of 
evidence as to the nature of his parents, his mother didn't behave in 
the best way but she did act out of love and you can't judge his 
fathers actions after he left as being under a potion was the same in 
the real world as being given the date-rape drug! He was raped by the 
mother over quite a few months so having nothing to do with her 
afterwards is perfectly understandable (although finding his child 
would have been ideal but he would never have known the mother was 
dead).

By the sound of things Harry's upbringing was a lot worse than LV 
could ever have imagined so why wasn't he evil? Why didn't he let all 
the fame go to his head? 

LV seemed to be evil from an early age, it was never explained why, 
and even when he entered Hogwarts things could have been different 
for him, he could have changed if given support. DD at least knew of 
some of his problems and perhaps should have helped him early. Maybe 
he was power hungry but you can be good and perhaps have just as much 
power, look at DD!

LV in my opinion was capable of love, he loved Hogwarts and it 
remained in his heart for the rest of his life so it's just this i 
can't understand...

Why was he bad?