Ms M, sorry for not replying sooner. His lead, his responsibility imo. You need to let him know that you think him capable and also for him to find out what the world is like without your help.
Even if he says that in court will you accept it then? Is that what you need for acceptance? You can work together on things but not the divorce papers if it isn't truly what you want. Don't be obstructive but you don't have to actively participate - act as if you are sure he is perfectly capable/ have faith in him handling it.
The whole 'will they realise after you get a divorced'... I don't know, it is a difficult one as do you think that he still blames you for stuff? If so you could leave him alone as I have done with my h but and I really don't think he blames me either, he just hasn't found the way back either because he doesn't want it or is not capable yet. Unfortunately I think it is the old saying time will tell.
People say that once you let go they come running back... but does that mean divorce? It is difficult, can you let go without helping him with the divorce. What do you want - identify what you are angry about and then put it to one side or let it go, that will allow you to see more clearly as you won't be blinded by anger.
I can see you are torn, I'm right there with you Ms M!