HARASSMENT HAS NO PLACE IN A CO-PARENTING RELATIONSHIP
A co-parenting relationship isn't ever easy, but it is necessary if you share children. Having an ex who is harassing you can lead to even more challenging situations than what you would normally have to deal with. There really isn't room in any parenting relationship for one parent not treating the other with complete respect, so you should think carefully about how to handle it if you find yourself in that situation.
One of the best things you can do is to set clear guidelines for all communication between parents. There needs to be an expectation set for speaking to each other, whether it is face-to-face, over the phone or via electronic communications like emails or texts.
When there are issues with harassment and respect, you should consider using only methods of communication that are recorded, such as text messages. Having correspondence in this manner might be the limiting factor that helps to keep your ex in check while you are trying to work things out regarding the children.
Another point to remember is that you need to ensure you don't try to return the harassing behavior with the same. Instead, stick by your own morals and behave respectfully so that you are able to have a clear conscience and don't have to worry about how your actions might be viewed in a child custody case.
There might come a time when you have to do something about the behavior of your ex. Speaking to a counselor or your attorney might help you sort things out. Court involvement is sometimes necessary for these cases.