I have incredible relationships with my son's aunts, uncles and cousins, to the extent that I probably talk to some of them and see them more than my ex does. The thing that has helped me with these relationships is that my ex's name never gets mentioned. The only questions I have answered is does he see his son because at the beginning he didn't. I will also talk about the visitation schedule because it relates to planning get togethers. That's it. I check my anger and frustrations at the door because they have no place in my relationship with the rest of his family. I understand that this is odd, but it works for me and makes for a good example for my son as he grows up.
We all have those days where we want to strangle our ex (even married people have those days), but I keep telling myself to be the bigger person and show my son how to treat others. It is hard to not respond in anger, but IMO, my ex is usually trying to pick a fight. If I don't show emotion when talking to him, he can't win. If he is rude, angry or inappropriate, I just politely walk away. (and document it for a future custody case) My son is 5 and he sees this. I could not believe during one of our exchanges when we got in the car, my son told me, "papa was rude". His dad didn't say good-bye because he was mad at me. Be the bigger person. It is not easy, but in the long run, you will be a much happier person.
Right now I'm redefining my dreams. In the last week, I realized that I have lost not only "our" dreams, but MY DREAMS. While every mother helps their children achieve their dreams, I believe the best way to help them is to show them how to set goals and dreams and follow them. I started a thread about what is on your bucket list as part of putting my dreams in writing. I want to set foot on every continent of the world. I want to participate in a triathlon. I want to be happy.