Rob, I'm having similar results. I have gone VERY dark - I don't answer any of her calls at all, just check voice mail. I also only respond to texts that concern the kids.
At first she was nasty as well - put up pictures of OM, etc. She also refused to talk to me as well. I simply kept dark and sweated it out. Then she started texting me about the kids, and slipping little conversational things in - I am still simply responding with "OK".
In my case, it is probably too late, so my focus is to simply put myself in a situation where she cannot hurt me, and cause as little hurt to the kids.
It is having an impact - I'm seeing where she is feeling the vacuum, it's whether she cares enough or not.
It is an effective technique - whether you go completely dark as I have, or "dim" as you are doing just responding as necessary.
It's funny how a WAW will get all indignant with you - even though they are the ones breaking up a family, marriage, etc.
