Unfortunately, co-parenting gives an abusive or narcissist parent a clear path of unintended court-sanctioned abuse, power and control of the ex-partner and the children, instead of protecting the well-being of the child. Co-parenting can give rise to all sorts of emotional terrorism when involving an abuser.
Abusers find out quickly ways to control you as your life unfolds beyond divorce. Suddenly, you might realize that the joy and happiness you felt about getting free of an abusive partner is gone as you see that you now have to content with an abusive co-parent. There is no divorce from that.