Tips for talking to kids about divorce (from Psychologytoday.com):
Don't assume how kids will react. Kids might be sad, angry or even relieved by the news. Let them feel all their feelings, even if they're confusing to you.
Really answer their questions. Instead of saying things will be "okay" give details and responses to kids' questions. When they understand what's going on, they'll be able to process their feelings.
Be thoughtful about the setting for the conversation. Kids remember learning about an upcoming divorce for a long time. Choosing the right place and time can make the memory less traumatic over time.
Check out these titles to help you start a healthy conversation.