Seperation?

I don’t know what to do. My husband moved out 3 weeks ago. We argue alot, he leaves to his grandma house, but this is the first time he’s refused to come back. He says he wants to fix our marriage but don’t want to come home. He’s also a narcissist who believes everything I do is wrong and I’m the problem. Along with being a compulsive liar. But I was willing to go to therapy and fix things. He don’t want to be with me. But he don’t want to get divorced! He keeps saying he don’t want to fight with me but our fights have anyways been about him lying or his actions. I have become somewhat codependent during our marriage so this is very hard for me. I told him if you want to live with your grandma you need to file for divorce. But he said no. He said he’ll just put himself on child support. Im so mentally drained. I get depressed and it’s hard taking care of the kids when I get like that. I just want to get the help I need and move on but he won’t let me. (He also makes all the money so he likes to throw that in my face too) any advice?