Hanging up in perfectly acceptable and not necessarily immature or anything else. When somebody's being unacceptable on the phone the acceptable response is to hang the **** up. You can soften it by saying, "It is unacceptable for you to be speaking to me this way so I'm hanging up now... CLICK MOTHER******!!!
OK, leave out the click part.
Sorry he's being this way TuffGirl. For some people the steps never click in. A super high percentage make it to step three and then stall. Step four is where it gets hard, because step four requires rigorous honesty. It takes a special person to be able to do steps four though twelve.
Cyranoak