Some things are impossible to escape, Lisbon will get hurt. Hurt physically, professionally and never meant for this to happen. He's in a catch 22 situation neither staying or leaving will save her. The only thing that will is capturing Red John. But then only if it's done 'right'. It won't save her if he exacts his revenge as he's always planned to do, or if he gets killed in the process. This is not his ego talking it's a matter of fact. Lisbon has become his best friend. He can see how much she cares about him. She forgives him over and over again so that she can stay close to him in the hope that she will be there at the end, in the hope that she will save him. He should have left long ago, but now he can't
Some things are impossible to escape. She will get hurt. Hurt physically, should Red John deem that a way to attack Jane, is to attack her. Hurt professionally as she will always be the fall guy for his mayhem. He.s 'Golden', she's just a cop, a dime a dozen. Hurt emotionally because he is her partner and best friend. If she doesn't stop him from carrying out his revenge then she will have to arrest him or even worse bury him. She should have walked away long ago and now she can't.