Need advice on how not to think our ex please?

It’s been 6 months since I left my ex who’s a narcissist. I went away for the weekend and I’m just getting back home. He enter my thoughts and I’m feeling sad now. All this man did was treat me like an option. He just took took and took and never gave a damn about me for 2 years. I’m doing great with no contact and deleted all my social media. So What the heck do I need to do to not continue having him on my mind? I must miss him ☹️.
Need advice on how not to think our ex please?
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