Why did your ex tell his friends he doesn't feel for Helen what he feels for you and then not act on it? I'm sticking with my previous answer, that as long as he can feel he's the victim of circumstances, trapped in the wrong relationship by the forces that be, he doesn't have to examine his own responsibility for how he got there. So, no, he's not a nutter--just a depressive. (Are you sure you want to take a depressed guy back? Who's to say how many times he'll cycle through these patterns if he doesn't seek help?)
As for the thoughtful present--those MLCers do have their "pockets of sanity," you know, where they see things more clearly for a brief period. Likely during one of those he remembered that you wanted those items, acknowledged he was a selfish friend who ought to put more care into picking and sending presents, and felt energized to change his ways. Then the fog swept over him again.... It's a lot like when the LBS thinks, "Look at the ways I've scrwwed up in my relationships, from now on I'm never going to x, y and z." But you have to make a great number of changes to transform yourself, and you have to continue to be aware of your shortcoming for the changes to stick.
Or maybe he thought he was losing his backup-girl, and so racked his mind for what would show he cared, or he'd done something nice for Helen and then felt guilty about you--but does his "reason" really matter? Does he even remember or understand why he did it?
Once you start channelling all the energy that you lavish on questions about Ex (and it's great that you're becoming less and less "depressed" when you do get caught up in his stuff) into your own life, your creativity and talent and power are really going to shine!
