My take on Harry's thoughts as he decides to go after Voldemort
Harry Potter had never thought much of himself. During early years of his life, he was 'the freak' or on particularly good days just 'the boy'. He never had any reason to think he was anything else. Then a certain letter came, and his life had changed completely.
Now he was the legendary 'boy who lived', the one who had vanquished a dark lord before he had even learned to walk. He now had friends, who cared about him and the entire world loved him. He said that he never liked the attention, but he knew that a part of him enjoyed the fame quite a bit.
but being the 'boy who lived' had consequences in the form of the dark lord he had supposedly defeated as a toddler and said dark lord's followers who wished to harm him. He Knew that his friends and allies would support him in his fight.
In his fourth year at Hogwarts, he learned that his friends were not as reliable as he thought they were. He took the glare from his fellow students quite easily but when his best friend, his brother in all but blood, Ronald Weasley turn on him he was heartbroken. His friends later apologized but the damage had been done. That year he learned that despite being in this amazing magical world, even among all his friends he would always be all alone. Suddenly being 'the boy who lived' was a curse which he had to bear.
Everyone wanted to him to be a hero, but he only wanted to be himself 'just Harry' but that dream went down the gutter when he learned that he was at the center of a prophecy and only he had the power to stop the darkness that was descending on the world.
The world needed a Hero, but He just wanted to run away. He almost ended it all, but he stopped when he thought of his parents who had given up everything just so he could live. He couldn't give up like that. He wouldn't let more children suffer the same way he did. That world was full of pain, but he wouldn't let Voldemort have it.
The World needed a hero, and it was going to get one. Get ready Tom because Harry Potter was coming to get you.