You didn't go "wrong" you just offered too much info. Keep pulling back when it comes to personal chatter, the more you do that the more she will wonder.
IMO if your child is sick when your W has her it is perfectly appropriate to IM/text for an update on how your sick child is doing. But that is ALL you should be discussing. If your W asks anything else or even tries to slip in any tiny bit of chit chat kindly say "thanks for the update on daughter, gotta run!"
The WAS likes to make the rules - in this case she will only speak to you about the kids. So follow the rules she dictated and let her wallow in that for a while. Its really the only way to "train" a WAS that they can't have both. The less she knows about your life the better.
And, just to shake her up a bit when you do get the new custody proposal she is sending you I would send it back and make it *very* official looking with both of your full names, the full names of the children, the date in which the agreement was sent and when this particular agreement will expire and a new agreement will be negotiated. She wants it all about business then make it ALL about business and treat this as you would a formal business proposal. I would also electronically initial it and ask her to do the same and return the initialed document to you within x days.
Also, this is sort of a random suggestion but I would start thinking about what kind of tradition you can start with your kids for YOU and YOUR KIDS ONLY this Christmas. It doesn't have to be about money or tons of gifts. Make it something special that you and your children can do each year that doesn't involve your W or anybody else but you and your kids. And don't tell your W about it either as this has nothing to do with her.
