Hi, and hugs to you...
In my experience, the smug look came when he knew he had me controlled. Once I filed for divorce, completed it quickly while he said "what's your hurry" (as he lived with his GF)...then set up my own house with our kids and never looked back except to collect child support...it was ME who gave him the smug look. Because he had nothing over me anymore and I knew who he was. He could no longer have any emotion from me.
Give yourself control over your life and take his emotional control away...whether or not he wears a smug look won't matter to you at that point, because you'll be free. Remaining trapped will only continue to hurt you and keep you from healing.
Just my experience...