OK - you want some step by step coaching, here is what I think.
For the most part you handled that IM *very* well. I still think you are offering your W too much info about your personal life.
I would not have told her about the lost/stolen bank card, that you are low on money, that you are using a credit card right now for the basics or that you are trying to save money. Too much info. If you have your own bank account there is no need for your W to know what is going on with it. If she is tied to that account of course she would need to know about the stolen/lost card but if the acct. is solely yours then what was the point of telling her about it? Finances are now personal matters and since she said she ONLY wanted to talk about the children then ONLY talk about the children.
Wasn't one of her complaints the fact that she felt you couldn't support a family? Do you thinking telling her that you could not afford to take your daughter to McD's was a good or bad move? First of all, she shouldn't be offering you suggestions on where and how to spend time with your children. I simply would have said "daughter and I always find something fun and interesting to do!" and left it at that.
When she asked if you had plans and you told her what those plans were (moving couch) but it got cancelled you should have either said "yes, I have plans so I really need to run, can you go ahead and send the custody arrangement via e-mail so I have a few days to look it over and compare it against my schedule" I might even have added something along the lines of you wanting to get a firm schedule nailed down ASAP due to your busy holiday schedule.
When she asked why you cancelled dinner the other night you could have said "after giving it some thought I felt it best for me to have all custody discussion "on paper"... I am sorry I cancelled at the last minute but something came up". Then say no more - don't tell her what a good time you had. Let her wonder what came up and let her wonder why you want all custody talks to have a paper trail.
And be sure to end all talks/IM's first. Avoid all this needless personal banter. She is the one that dictated to you that she only cares to speak to you about the children so follow that. If and when she starts to reach out to you, you can change your strategy a bit but for now keep it VERY vague and let her wonder what you are up to both personally and legally. It wouldn't hurt her to think you are wanting "paper trails" about custody to perhaps plant the seed that you are in the process of getting the legal ball rolling.
I can guarantee you she won't like this and will start acting very bitchy but tough. She said kid talk only so you will follow that to a "T". She will not like that doesn't get to know everything and what you are up to. If she happens to ask if you have any legal plans I would simple tell her that yes, you have been exploring options from a legal standpoint and when you have something to discuss with her about finalizing the divorce you will let her know. But don't say ANY of that unless she brings it up first.
