It is very natural to miss someone or something, even when you know it's not good for you! However, if you want to see the light, you must put the work in and redirect your thoughts. Reflect and journal. Then ask yourself, what is it that you're really missing? Being in a relationship with a narcissist, it will never be about you. It's about them and their gain, only. Is that how you really want to live the rest of your life?