Difficult Conversations by Douglas Stone, Bruce Patton and Sheila Heen (of the Harvard Negotiation Project) was so useful in navigating a recent issue with my ex-WS involving the kids. It has also been healing, as the process it uses makes you look at how your feelings and identity are engaged in a struggle with someone else.
Some highlights for me:
1. I had to examine my own contribution to the issue, which was really hard. After a while, I realized that my contribution was (a) avoiding discussing the issue with him until it escalated to a crisis; and (b) if I'm honest with myself, I haven't been receptive to communication about the kids because I'm still a bit mad at my ex.
2. You have to determine what the purpose of your discussion is before you go in and decide whether it's even worthwhile to have a conversation.
3. Even feelings that you think are irrational can be expressed in a difficult conversation.
4. My views and feelings can be complicated and even contradictory and that's ok.
There is way more stuff in the book. It's like taking Brene Brown's stuff about being vulnerable, and giving a road map to actually putting it into practice.