My boyfriend is divorced. We have a six month baby.  Whenever we go out he call his ex wife and talk like friends or flirting and I have talked with him and told him to stop calling her because to me is like cheating and is rude that talking infront of me and is rude. Then he stopped talking to her because his kids also get mad at their mom for calling him because they know his dad is already in a relationship with me and don't want problems. I found out recently that they call behind my back and when their kids are in school...it is cheating or not? Their kids are teenagers. I told him that he doesn't have to talk with her that leave her have her own life. His ex wife is not dating anyone, she is single since they divorced.