Ex narcissist keeps bringing his new gf to all the places we use to go to/restaurants near my house. How do I avoid getting hurt/not let it get to me?

I broke up with him to see if he would change/treat me better seeing as he always complained/put me down/broke up with me whenever he didn’t like something. I always had hope he would miss me and realize how bad his life was without me. Now he is dating a girl really similar to me and even it’s been almost a year he shows her off (which he never did to me)/ takes her to our favorite spots. I know I shouldn’t let it affect me but it still hurts