As I continue reading Harry Potter and the Deathly Hallows, I have noticed that J.K. Rowling uses issues she sees in real-life in the Harry Potter books. For example, Voldemort's rise of power is VERY similar to Hitler's Nazi regime during the Holocaust/World War II. I think the character Rita Skeeter shows J.K. Rowling's portrayal of the media.
As we already know, Rita Skeeter has published countless lies about Harry, (especially during HP and the Goblet of Fire and HP and the Order of the Phoenix. So why is Harry believing her every word in the book The Life and Lies of Albus Dumbledore?
She is manipulating Dumbledore's past. According to Merriam-Webster, to manipulate means to to control or play upon by artful, unfair, or insidious means especially to one's own advantage. Rita only cares about publicity and money. Sometimes, she doesn't lie about things, but she is an excellent manipulator.
He had trusted Dumbledore, believed him the embodiment of goodness and wisdom. All was ashes....
"-but don't forget, Harry, this is Rita Skeeter writing."
"You did read that letter to Grindewald, didn't you?"
"Yes, I- I did...."
"I thought you'd say 'They were young.' They were the same age as we are now. And here we are, risking our lives to fight the Dark Arts, and there he was, in a huddle with his new best friend, plotting their rise to power over the Muggles." (pg 361)
Harry had trusted Dumbledore completely. He had idolized Dumbledore as if he were, you could say, "God." But the more information he hears about Dumbledore, such as his friendship with the notorious wizard Grindewald and his attempt to "rise to power," the less faith he has in him. This was so unlike him. Harry is angry and unsure whether to trust him or not. Hopefully Harry will come to his senses and realize that Dumbledore has made up for his "shady" past.