How to deal with a N when you have children together

My exN is supposedly getting married to the OW they have only been together I believe 2-3 months. We have a child together even though he doesn't see her right now (his choice) because he's mad that I have a restraining order against him but he still has rights. He left his place to move to another state with the OW. My question is when the time comes how do I deal with them in a mature way? Is it okay that I don't want to meet the OW and that I don't want to have any interaction with her? Is it okay that when I have to deal with the exN that I ONLY deal with him regarding my child? He's the type that believes everyone should be friends and I do not want to be friends with anyone. I just want to keep it strictly about our child and that's it nothing more and nothing less. How do you deal with the exN without seeming to be bitter or jealous?