JP does have two personalities, sort of. There is the French-Canadian pack alpha trying to make sure his people are safe and the one he displays to the people in his gang. That isn't to condone anything he's done, but slightly different from duel personalities. Kind of like a gay man trying to live a straight light. JP doesn't so much want to die, but knows it's highly likely for everything he's done, and that it would be fair justice if he did. He also realizes that he's found someone who can assume control of his pack and give them the protection from outside harm if he does die. Yes, Aiden has a lot riding on his decision. He has seen and experienced the gang first hand. His law enforcement training and basic instincts would be to destroy this person who has committed such horrible crimes, but he knows there is more to it along with everything the man had documented.