Defeating the most dangerous dark wizard ever when you're still in high school? When your super-powerful, super-wise mentor isn't around to help you anymore? Yeah, that definitely involves bravery—and probably a little insanity.
Harry has been forced to be super-brave since he was eleven years old, so he seems to be getting kind of used to it. However, the dangers around him are only getting more intense: the Ministry has fallen, there are Snatchers rounding up wizards, Voldemort's snake almost kills Harry when it disguises itself as an elderly magical historian…there's lots of scary stuff to overcome.
To make matters even worse, Harry and the gang start out pretty much totally clueless about where to go next on the whole Horcrux mission. So, they spend The Deathly Hallows, Part I in pretty much constant danger with nary a clue about how to make it stop. Yup: Only a fair bit of courage will get you through that.
Harry's reaction to cowardice shows us just how brave and honorable he is—he usually just keeps on fighting and doesn't get judgey.
Ron's issues aren't about being brave vs. cowardly. He's just a little susceptible to doubt.
We've seen Harry and his friends get angsty before. Remember Harry Potter and the Order of the Phoenix?
Well, in The Deathly Hallows, Part I, Ron's the one who's mad at the world. Or maybe just Harry. Anyway, he's having a rough time being out and about with Harry and Hermione, trying to find Horcruxes with basically no clue about where to look or how to go about destroying them.
Plus, he seems to think that Harry and Hermione have some kind of secret tryst going on, which definitely isn't making him happy. So, he ends up leaving the group for a while, and it's sad times all around.
Good news, though: you can't keep wizardry's favorite trio apart for too long, and with the bonds of friendship renewed, they start make progress on this whole Horcrux thing. And thank goodness. There's enough stressful stuff going on without the infighting, so can everyone just stay friends until the end of the next movie?
This movie really brings the importance of friendship front and center. Without friendship, Ron and Harry never would have been able to figure out how to destroy the Horcrux, right? No one—not even Harry—can defeat Voldemort alone, it seems.
The nail in the Death Eaters' coffins? The fact that they don't form real friendships. How can they possibly sustain their little group if there's nothing but greed and evil to hold them together? A group of individuals who are only out for themselves…yeah, that can only go so far.
We thought things had been pretty dangerous and difficult for the young wizards up to this point, but that was all nothing compared to what they're facing in The Deathly Hallows, Part I.
Harry, Hermione, and Ron have to keep going on the quest to find and destroy Horcruxes, but it's pretty tough going—and the fact that they don't have a clear direction, plus the evil influence of the one Horcrux they've manage to find, plus the stress of having people constantly after them and their families…it basically brings our heroes to the breaking point. Particularly Ron.
Luckily, everyone finds their way back to each other, but the whole Horcrux hunt really forces the kids to realize where they're strong…and where they so aren't.
Harry is tough, sure, but he does have a weakness that his enemies consistently capitalize on: his intense fascination with his lost family. That fascination is partly what brings Harry to Godric's Hollow on Christmas Eve…where Voldemort's snake is waiting, disguised as an old woman (naturally).
Ron does leave his friends, which isn't great, but the fact that he overcomes that weakness? Totally impressive, and we admire him more for it, once it's all said and done.
The Deathly Hallows Part I begins with a whole bunch of double-crossing and betrayals. Snape betrays the Order of the Phoenix. A guy from the Ministry of Magic becomes a Death Eater, which is probably how the Ministry ends up falling.
And that's just the beginning of the movie.
So, yeah, the Death Eaters are definitely gaining traction from everyone's willingness to rat or turn on each other. Luckily for us, Harry and his friends are (for the most part) pretty loyal, so they manage to fight against this nasty tide in their own relationships…eventually.
Ron only ends up betraying Harry and Hermione by leaving because he thinks they've betrayed him—and that's all the result of the Horcrux's powers. Voldemort's influence is all about sowing doubt and fear in others.
Ron really screws up when he thinks that Harry and Hermione could ever betray him, and even more when he leaves them. Sure, he comes back, but doubting and then abandoning his friends? That's serious betrayal.