1. Alter Your Method of Communication
Look back over the course of your co-parenting relationship. When do you seem to argue the most? Is there a particular mode of communication that makes it easier for your contact to disintegrate into accusations and name-calling? If so, then you need to change the method of communication.
For example, if your ex calls your home late at night, turn off the ringer and follow up the next day through email. Or, if he or she constantly hounds you with text messages, limit your response to a simple acknowledgment that you received the message.
2. Defer the Conversation
Another useful tactic for dealing with an argumentative ex is to defer the conversation to anther time. For example, if your ex typically uses the children's drop-off or pick-up time to initiate trouble, suggest that you both wait to discuss the matter in private, over the phone, or through email. Many co-parents find it helpful to schedule a weekly email or telephone co-parenting "meeting" for this purpose.
3. Refuse to Defend Yourself
This is an extremely effective way stop arguing with your ex. After all, when you refuse to engage in unhealthy ways of relating with one another, you ultimately change the existing pattern of your interactions.
For example, if your ex is attacking your parenting style, refuse to engage in a defensive explanation of your actions. Instead, realize that just because he or she is upset about a particular issue, and that does not mean that you are a "bad parent," and--in many cases--having an argument about it will not bring him or her any closer to seeing your point of view.
4. Acknowledge the Other Person's Perspective
In fact, a lot of escalated arguments can be avoided simply by acknowledging what the other person is trying to say, or how they are feeling in the moment. For example, if your ex is blaming you for not making the kids do their homework before dinner, respond with "I hear what you're saying. You'd like me to make sure the kids do their homework before dinner. You've made your point, we don't need to discuss it further right now. I've heard you." At a later time, you can think about what he or she was trying to say. If there is merit to the request, you can follow through on implementing it. If not, you can simply acknowledge the request for what it is: a parent who wants increased structure in a certain area of their child's life.
5. Let it Go
Finally, in order to protect yourself from the poison of constantly feeling like you're in a battle with your ex, there will be times when you simply have to "let it go" and agree to disagree. Even if you had stayed together and raised your children as partners, there would be plenty of things you'd disagree about. As different individuals, your parenting styles aren't going to be exactly the same, and, fortunately, your children already know your expectations and are able to adapt to these differences. Choosing to let go of areas where the two of you don't exactly agree can help you focus on the influence you do have over your kids, and stop arguing with your ex so that you can finally put an end to the constant tension between you.