How do you move on when your ex keeps showing up in your life?

My breakup was a few weeks ago, and I feel like I can’t escape it.

The relationship was over 2 years long, and while I know ending it was probably the right decision, I’m still grieving it pretty hard. What’s making it worse is that my best friend recently started dating one of my ex’s close friends.

I’m genuinely happy for her, but now my ex comes up constantly. If they’re making plans, he’s somehow adjacent to the conversation. If she’s hanging out with her new boyfriend, there’s a chance my ex is there too. I hear updates I didn’t ask for, wonder what he’s doing, whether he’s dating, whether he’s happy, etc.

It’s like every time I start to get a little distance and feel better, something pulls me right back into thinking about him.

I don’t want my friend to feel like she can’t talk about her relationship, and I don’t want to be the bitter ex. But I’m struggling with how to heal when my ex still feels so present in my life through someone else.

Has anyone dealt with something similar? How did you create enough emotional distance to actually move on?