I don't know that you should go out and file for D. Only you can decide that. And as DnJ says, it'll likely result in you getting D'd (though hate to say it, unfortunately you're probably on that path anyway).
What I do know for sure is you need to change your mindset to one of much closer to what Kind18 says. When your W said "maybe she will just move away" you know to where she was referring. Start acting like you're too good to be cheated on and won't accept it anymore.
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