Harry’s remarkably hard to get to know, isn’t he? Remarkably hard to get close to? The only people who seem to really like Harry for himself as of the beginning of OotP are Hagrid, the Weasleys, Hermione, and Sirius.
How sure are we, really, that this reflects some flaw in Harry?
Because, consider two final things.
First, it’s convenient for Dumbledore, isn’t it, that Harry grows up with no attachment to the Muggle world, neglected, so emotionally deprived he is ready to latch on to the first friendly faces he sees? By some odd coincidence, his only relatives hate and fear magic and transfer that attitude automatically to their new ward. And by yet another odd coincidence, Harry’s first friends are among Dumbledore’s staunchest supporters.
I’m disinclined to trust in coincidences that just happen to further the Twinkly One’s plans. In fact, that are integral to it. What would have happened to Dumbles’ plans had Harry been loved by the Dursleys and absorbed their attitude to magic, or had Harry’s first friend been a Malfoy rather than a Weasley?
Secondly, Hermione told us, on the authority of the books that she stole from Dumbledore, that it is dangerous to become “too fond of or emotionally dependent on” a Horcrux object. If someone makes the error of getting “close emotionally” to the Horcrux, the encased soul-fragment may be enabled to flit out and possess the fond fool.
Harry is a Horcrux, and I’ve previously suggested that Twinkles was perfectly cognizant of that fact when he parked that Horcrux with Lily’s Muggle relatives.
I had thought that it was shocking of Twinkles to subject poor Petunia (and her family, and all the Muggles in Harry’s neighborhood and school) to the risk of being possessed.
But maybe he didn’t.
Maybe Twinkles had taken precautions against that eventuality.
Petunia’s family and neighbors, and the kids at Harry’s school, were, after all, only at risk of possession if any of them became fond of the boy.
The WW has Love Potions. And their antidotes. Entrancing Enchantments. And, presumably, their counterspells. The Veela-glamour… and there must be spells to resist that, or the refs would have given the match to Bulgaria.
If attraction/interest, whether sexual or otherwise, can be artificially created or enhanced by magic, might it not also be artificially suppressed?
Is there an enchantment, or a potion, that inhibits attraction/affection/love from developing? Oh, maybe no spell could stop True Love any more than it could start it—but could one, perhaps, put people off initially? Leave them cold? ... Now, supposing there were such a thing and Twinkles had used it on the Harrycrux, consider Harry’s introduction to the WW. Not only does Harry need to be recruited into a political camp, but also the degree of danger posed by the potentially-infectious Horcrux must eventually be evaluated. Harry is venerated as the Boy-Who-Lived—at some point someone’s going to be fond enough of the idea of Harry to be at risk, even if s/he doesn’t actually like the boy for himself.
So, it would be prudent to select a few companions for Harry whose subsequent reactions can be carefully monitored.
Give Harry, for the first time since he was a toddler, people who are not magically inhibited from liking him (or who he’s not inhibited from liking), let friendships develop, and watch how long it takes before the friends become possessed, and what the signs are.
Now, since part of the point is indoctrination, one would naturally choose Harry’s possible friends only from among people who strongly hold the correct beliefs—the dogmas of the headmaster’s infallibility and the inferiority of dirty Slytherins, for example.