How do I stop contacting my ex?

I hate that there’s always something that brings me back to him. I know that its really over. But seeing his mom yesterday that is worried about me and came just to check on me THAT leads me back to him again. I can’t say the other reasons too but A LOT happened that always gives me a reason to reach out. I always ask God why is he doing this to me honestly its been ruining my pace of moving on. I don’t wanna reach out ever again. I blocked him everywhere and yet I texted him on imessage just to say about his mother. I think that won’t matter anymore. But whenever I’m trying to move on, there’s always this very important happening that is related to him makes me wanna crawl back to him. I know its not healthy. Its over for him. I want to stop.