Sounds like you made the right choice in leaving.
I reckon once you get used to where youre living now the sounds if your friend moving around won't even register with you. Alternatively you might invest in some ear plugs. Sobriety us much easier when we accept other people and their quirks rather than try to change them. Will you be there long term anyway, or iis it just a short-term and emergency arrangement?
I remember talking to an old timer in AA about my father, saying all the things he'd said on the phone that day that had driven me bonkers. The old timer said "That's terrible Berry. Do you mind me asking - has he ever said stuff has been like that before?" I replied that yes, he said stuff like that all the time and always had done. "Oh. " he said. "So why did you think today was gonna be different?"
Jeez, he made me mad. But what he was saying was that my expectations were causing me problems and making things worse (for me) in my dealings with my dad.
Sound like your ex is as unlikely to change as my dad is. So, expect him to behave as he always has. No doubt he is just reacting as ever with the silent treatment. Perhaps to punish you, or perhaps because that's all he's learned from his own family over the years and this is all he's capable of. If there's been no meaningful communication in the past, it's unlikely to start now. Why not just block his number and resolve not to think about him. You left for a reason. What point is there in engaging with him now?
BB