Can I ask how you think I handled the Xmas decorations badly? I felt this was a 180 for me. I also think this was also the start of the W moving on / going dark / NC / whatever you want to call it.
To me it just seemed like a guy who was trying to be difficult. So much drama involved. Put her stuff in a box and drop it off at her house when you know she or Mr Wrong arent there. Send her a text once it is done. "Dropped off your half of the decorations, hope you have a Merry Christmas" That sounds a like a very strong guy who isnt letting her petty stuff or her awful choices ruin his life. That is what will bring her back.
I think there was an issue with your wife wanting to send some gifts for your daughter. I think you should let her and thank her afterward via a card. "Daughter loved the gifts, thanks!" No loves, no miss yous. Just strong, positive man getting on with his life.