At the risk of irritating / offending everyone here...
My initial reaction is that Joe Demko is exactly right, Sean is a very ill individual who needs more help than your Aunt can give him (i.e. professional help).
However... there are other things going on, that might have shaken him up, besides the sight of your AR-15.
Sean finds himself:
1) in the company of people who are comfortable with guns, of which he has no experience, but plenty of negative propaganda.
2) one of these people is your Aunt, who he thinks he knows intimately (and finds he does not!).
3) "out in the country" (I think your location said Utah) whereas he is a city-dweller.
He is *compeletly out of place* and dependent upon the good-will of people to whom he thought he could relate, but *absolutely* fundamentally does not understand, and has been taught to fear (by his general upbringing / urban ethos). Sean is cast adrift with nothing to hold on to - imagine waking up one morning to find that everyone you know is really a stanger in a rubber mask, or an alien from another planet... you might be moved to tears as well.
His world was severley shaken. Give him a hand. Talk to him; make clear that, although you come from radically different backgrounds, you will not harm him and want to share your world-view. Maybe offer to take him shooting, with a .22 rifle - tell him straight out that the quickest way to defeat fear is to confront it, and that he will not automatically turn into a killer as soon as he (G-d forbid!) holds a gun in his hand. People *can* grow up, at any age, given a little gentle guidance (and the will to do so).
With that said, I can't imagine anyone who is basically sound, reacting as you reported your Aunt described. Still, I've seen some radical reversals in people who "thought" they hated guns... and started shooting Highpower or F-Class, and posting great scores. Sean might just need help taking off his blinders.
Purrrs,
BobCat
http://www.bayourifles.org
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