still scared

 In the process of trying to start to divorce my ex narc, I see that although its been 10 months he still scares me. I know he will be mad about me not sharing my tax money. I know he will not take care of our mutual affairs and he will try and make me pay his debt. He is so used to me taking all his mistakes and letting him off the hook. He thinks he can still fool me, he doesnt know I have changed and see him. The only thing is I am still scared. why?