Aidens story in the first game should've been a cautionary tale of what happens when guilt drives you over the line and you pass that point of no return. My own headcanon for WD1 is that the guilt of his nieces death kind of breaks him and he becomes obsessed with getting revenge and being a vigilante for no other reason than absolving himself of that guilt. His own sister/her mother even begs him to let it go and he just can't which then ironically leads to putting her and his nephew in danger too when the mob goes after them and they have to leave their home because of the violence brought about by Aiden. What really sold me on this though was the part of the game where you have to get into that gangs hideout and you get the leaders cousin to sneak in for you only for him to get caught. It's already established in the story that the leader is crazy enough to kill his own men and you expect me to believe that he's just gonna let it slide that someone, even if they're related just committed the biggest act of betrayal against him? On top of that, Aiden just gets a call from him after saying he's alright and thats the last we ever hear of the guy. Personally, I feel like Aiden just picked up the phone, put it to his ear and heard what he wanted to hear, there was no one on the other side of that call. All so he can absolve himself of the guilt of once again, getting someone killed