Change your perspective

Here are some suggestions that might help:

1. Try to get your ex off that pedestal in your head. I know how you feel. For months, I felt my ex was the perfect one, the jewel - but the fact is they left us. If they were the jewel that we consider them to be, they should have stayed, right? They would have chosen us, they would have fought for us, right? But, they didn't.
2. You're hurt. You're nursing a deep wound within your heart. You need to heal. If your knee gets injured, what do you do? You let it heal, right? By talking to your ex, you're just inviting pain into your heart. You're sabotaging your healing.
3. "But I just want them to understand, that's why I reach out to them. I want closure." The truth is there's no such thing as closure. Let's say you did get closure. Would that make it hurt less? The fact that they didn't stay for you means they weren't the right person for you. Let that be your closure. Closure is a means of procrastination on your healing. Please don't wait for it.
4. Try to make an action plan for times when you get triggered to want to unblock and dial/text. My plan includes something like going through very specific instances of my ex gaslighting me. I've a huge list of reasons my ex was bad for me - and I keep revising it. You need to keep reminding yourself of those red flags.
5. Lastly, please be kind to yourself. You poured your heart out to somebody. You fought for somebody. It's not easy to just start a new career, or pick up a new hobby, and go on with life like nothing happened. You're hurt, but I promise you'll get stronger.