Character Analysis
Aron is the son of Adam and the brother of Cal. He is the perfect little blonde angel of the Trask clan and everybody is head over heels for him, but really he's kind of a jerk. He's got a very holier-than-thou attitude: he finds his father annoying, he needs his girlfriend to be perfect, and the news that his mother isn't a saint is, like, the worst thing in the world. But he is also the Abel of the story, so things don't end too well for him.
The Apple Doesn't Fall Far From the Tree
You know how Adam sees the world in naïve terms? Aron has got the Adam genes for sure. In the same way it is for Adam, the world is basically a confusing place for Aron and he needs other people to look out for him.
Fortunately, pretty much everyone is willing to do that because Aron is so darn pretty and innocent looking:
Aron drew love from every side. He seemed shy and delicate. His pink-and-white skin, golden hair, and wide-set blue eyes caught attention. (36.1.15)
Think of Aron as a puppy that someone left on your doorstep. Of course you're going to take care of it.
On the other hand, Aron is a black-or-white kind of person: shades of grey or moral ambiguity do not register for him:
He was unchanging once a course was set. He had few facets and very little versatility. His body was as insensitive to pain as was his mind to subtleties. (36.1.15)
For Aron, bad is bad, good is good, and there is no in-between. That's not a very healthy way to live, though, because the world is not at all like that. It means, for instance, that when you find out that your mom isn't a nun, you have to go do something dramatic like join the army with a death wish.
It also means that Aron is constantly bugged by the vague dirtiness around him, and thinks that he can somehow escape it by becoming a minister or going to college:
Suddenly Aron broke down. "I want to go away. It's a dirty town."
"No, it isn't. It's just the same as other places." (43.3.77-78)
That second voice of reason belongs, of course, to Lee. Because everything with Aron is either all bad or all good, he sees a whole lot of bad. He also puts a big burden on poor Abra, because in his mind she has to be all good. And who wants to be all good?
Mommy Issues
Speaking of which, another reason why Abra has to be all good is because in addition to being Aron's girlfriend she also has to be a stand-in for his mom. Gross, we know. As Abra says,
"I figure Aron needed a mother more than Cal did. And I think he always blamed his father." (44.1.20)
That makes a ton of sense, given Aron's general helplessness and his attitude toward his dad. Remember the scene when Aron and Abra are kids hanging out under the willow tree, and Aron asks Abra to pretend to be his mother and his wife? It seems that, for Aron, the lack of a mother was a huge gap in his life that he then filled in with his own idealized creation. Abra and Lee explain it best in one of their kitchen-conversations:
"I think Aron, when he didn't have a mother—why, he made her everything good he could think of."
"That might be. And then you think he dumped it all on you." (44.1.55-56)
We've been talking a lot about how Aron can't think in nuances. By not knowing the truth about his mother, he could essentially turn her into any kind of person he wanted—and, being Aron, he chose the purest of pure visions. Not to get all Freudian, but his imagined mother then became the model for his ideal woman:
[…] of Abra he made his immaculate dream and, having created her, fell in love with her. (47.3.3)
Aron does to Abra exactly what Adam did to Cathy: he makes her into something that she is not, and can't deal with the reality of what she is. Talk about all men marrying their mothers.
Aron's Timeline