However, I would seriously consider a change of employment. I know that is extreme, but working with an EX has to be some kind of torture in third world countries. I would find a new job as soon as I could.
I was going to float this idea as well. It'd be a big change but would help your emotional state to see STBXW less, get away from the office drama, and would lead to meeting new people.
No idea what you do, but in the current employment market it might even have the added bonus of a significant pay increase or promotion. I'm a manager with several open job postings and I can tell you it's difficult to find candidates right now and prospects are getting good offers (at least in my industry).
Me:39 Ex-W:37 M:7 T: 9 S:6 D:3 BD/IHS/Confirm EA/PA: Feb '20 OM1 affair ends: May '20 W/OM2 & moves out: June-July '20 W files for D: Jul20 OM2 confirmed: 9/2020 Divorced: May '21