dumbledore

in short, albus is afraid of himself, he’s afraid of the aspects of himself that make him human  ---  his emotions, intimacy, his power, his character flaws, etc. he thinks that as soon as he lets his emotions get the better of him, as soon as he starts to care about someone as a person rather than abstractly, that he’ll become blind, make poor judgments, and something Bad will happen because being cleverer than most men his mistakes are often greater. ( which is why he ghosts harry for an entire year, and why he basically expected that to happen ) ( which is why his boggart is ariana’s corpse  ---  yes, he fears he was the one who cast the spell that killed her, but it represents a larger problem of him being fearful of himself because of what he is capable of ). so, he denies himself personal relationships of all sorts ( no romantic relationships, no friendships [or at least hardly any. there are no doubt a plethora of people who think they are albus’s true friend, but in reality albus does not see that way in the least.], nothing but professional relationships and those between a teacher and his students ) and forever has a plate of glass between him and the world, because he thinks it’s for the best for everyone.

and then he defeats grindelwald in a duel, basically ending wwii and saving the world single handedly, and he becomes viewed as a savior, as an all-powerful, magnificent figure  ------ and albus goes ‘okay’ and accepts it. he molds himself to this Idea(l) to the point where he becomes known as the champion of the downtrodden, of the light, of love, (etc.) and eventually people begin to use people’s opinion of dumbledore (and his opinion of them) as their basis for Moral Rightness. 

he isn’t a person to the rest of the world --- he’s Dumbledore, an idea, an ideal, a symbol of hope and goodness. and albus encourages this, plays this up with his ‘wise, eccentric, old man’ act (which is an act. yes he has a Particular sense of humor, but the more something sounds like wise, eccentric old man nonsense, the more he’s bullshitting you . . . . or, he’s just trying to make you more comfortable around him. he uses it for both ), because he is honestly more comfortable being an Idea than he is being a human being, and because, in his mind, life is about martyring yourself for something ( the good of humanity / the world, a cause, and, in albus’s personal case, the memory of / honoring his family that he so ruined ). this is why rita’s book is so singularly shocking when it comes out.

( i think it was also very easy for him to be comfortable with the idea of ... being a symbol for the magical world because he felt so Othered by it his whole life for various reasons. he has already come to terms with the fact that he doesn’t “belong” so he’ll become something else for them instead --- a leader, a symbol of hope, etc. after all, if one is extraordinary, is it not their responsibility to use that to help others? )