Well, it is better to run it by here before you send it so you can handle the feedback.
I think you didn't really validate and ask her where she specifically felt misunderstood because you want to improve the communication (she is telling you that is a huge issue for her)...
The rest is quite a lot to throw into an email that is supposed to be addressing what will happen with the kids.
You get my drift? Best to keep the issues separate and clear and exhibit that you can focus on the specific issue she brought up, which was that regardless of what you think, she feels misunderstood. And, it would behoove you, for your own sake to get really clear on what the agreement is, cuz as I read it, it is not clear. It sounds like she intends to use her discretion regarding what kind of contact the kids will have with OM and she doesn't want to have to run it by you anymore.
