Stop giving the ex prime real estate in your mind. Nothing you think, wonder, ponder, analyze does anything to change the situation. As simple and difficult as it sounds start living your own life. Deciding to put the house on the market and having to throw out tons of stuff has been cathartic for me. I later found out ex remarried the day of my tag sale! Fitting.
I have a friend who's considering divorcing her spouse. After giving her a list of books to read I asked her to consider doing the work to make the marriage work. But once someone starts seriously deciding to leave, they make a plan, they start detaching ages before they walk. Leaving is something planned and executed.
So.. with the divorce that chapter is toast in the loaf of your life. I get caught at times thinking about ex and Mrs. ex, argue in my mind. But you know when that happens? When I'm bored, restless. It's a type of masochistic brain masturbation that hurts and goes nowhere but downhill.
Hellloooo.. why oh why do I do that to myself? Let's see.. I'm punishing myself, I'm fearful, I'm scared, insecure. It's my choice how I live my life.
You're great, you're wonderful, making strides. Leave him behind like toilet paper stuck on your shoe. Scuff it off and move forward. Be glad you're learning what it takes to truly love yourself and move forward.