Its kinda hard to emphasize with. But its basically deep guilt and regret. His last life he lived his life like the character he is playing not a mafia boss but ruthless didnt care about others and only viewed others as his stepping stone to the top. Because of that he abandoned the only one who still cared for him even when he acted like that his Mom. Seeing his mom die a useless death like his previous life hes basically getting PTSD. Its a form of regret u can’t actually understand until it happens to you. Think of someone u care about deeply u literally cannot think ur life would be the same without them and u (stupidly) framed them for murder its not this drastic but its kinda that feeling
It also doesnt help that the people who he once admired and lifted him up in his previous life is not looking up to him and saying he is an inspiration. He cant tell them the truth that his values come from the people telling him that so he doesnt want that credit
I'm probably too emotionless that I can't really understand what he's struggling with lol