Harry has faced Voldermort many times now, successfully. He may have escaped sometimes, but he's still alive at the end of Year 6.

In each book Harry and Voldermort are contrasted, with Snape in the middle going between good and evil. The fundamental difference that separates these 3 is how they work with, use, love, hate, other people.

Harry's ability to love has kept him alive. Harry has friends, who are smarter than he is, kind, nurturing, loyal, etc. The closest thing Voldermort has to a friend is the snake. He uses fear to control. Even though Voldermort is growing stronger, Harry's support is growing too. Dumbledore's theory was that love saved Harry once and as long as Harry can continue to accept the help of others to actually live - and live in a world without Voldermort.