Actually Bruce Wayne was supposedly just another guy killed during Bane's reign.

And I don't think it's too hard to believe he found a way back to Gotham and a way to fix the autopilot.

And Fox said long term he could prove fraud with the trades, which means eventually Fox gets all the money back to Wayne Enterprises and continues to be a good president for the company. So Bruce wouldn' have to worry about that.

And Bruce finding a life to live is just as much about making Alfred happy as it is making him happy. Batman was Bruce's way to follow his father and help Gotham. Bruce finding a life is his way of following the man who really became his father, Alfred.