Honestly - if Aaron did that with me and we're married, I just don't think I could forgive that. I hate when someone goes to such a length and the like to find out what is going on.. if anything is going on.. or just being nosy. I value trust above a lot of other things and with out trust, there's not much there. With out trust there will always be doubt, accusations, second guessing...
Obviously you're having a terrible time getting over it. Good.. it just isn't something to forget about. If he created a whole other fake person, just to speak with you.. just to keep tabs on you.. then that is something major. I think it goes farther than being insecure... it is more than borderline possessive. Any way you look at it, its just not a healthy thing to be doing when you're in a relationship.
Better communication may have eased his mind a little, but it seems that he wanted a way to keep tabs on you.
Yeah, you're right it was a completely overblown breach of trust on his part and if what has happened with you - happened to me - he wouldn't be in my life anymore. It is just beyond anything I can forget/forgive.