I've gotten to the stage in my life where I have trouble letting things go. If someone has hurt me, I try to reconcile the issue, or at least resolve it to the point where we attempt communication, and if nothing can be reconciled, then the relationship is let go. In talking to other folks in the past, I've gotten the advice just to let the relationship fade away, but I have trouble doing that; I'd rather just resolve the issue and be done with it.
So as such, I had sent an e-mail to someone I care a lot about, but whose behavior was (likely unintentionally) hurtful, telling her why I was hurt at her complete lack of response, asking if I had done something to hurt her (I can't apologize and try to fix the wrong I've done unless I know about it), and asking if she was just not interested in developing a relationship anymore, in which case I would leave her alone.
Her response was such that at least I heard that I had not done anything wrong, that she was busy doing various things (and I got some details in terms of what she was up to), but that included reactions that interpreted my e-mail as sending her several angry e-mails, incorporating (more) drama into her life, and essentially a slew of misinterpretive understanding of what I had said and been attempting to do.
I apologized for anything I might have said that could have been interpreted as hurtful, and at least attempted to explain why I was hurt by her behavior. What it comes down to, largely, is that this person is still young, extremely unsure of herself, and at a point in her life in which she finds herself extraordinarily overwhelmed by events she's experiencing for the first time - and to the extent where she doesn't feel like she has time to breathe, let alone e-mail anyone.
I replied that all she had to do was tell me that she was busy; she didn't even have to go into detail about what she was doing, she just had to communicate to let me know she was busy. What this all boils down to is that I think that even when people are older, they don't realize that all they have to do is tell people when they're busy; if one falls off the face of the earth, one wonders what's going on, and bad feelings can ensue.
It'll probably be awhile before C. feels she can trust me again; she's generally distrustful of anyone who's an adult, no matter what they may or may not have done. I can't help being an adult, and I can't help if she's decided to mistrust me simply because I'm adult.
Nevertheless, at least the lines of communication remain open. I think (hope) she'll remember to reply once in a while to e-mails, and I'll remember not to worry if I don't hear from her all the time.