I am one of the ones who chose to walk away quietly. The method you choose has to be your decision. Some people need to DA for their own emotional well being and peace of mind, others are fine with the walk out or fade away method. Let them do whatever they choose to do when they see your christmas tree in the front window.
Go out and begin living your life to the fullest. Enjoy watching your children blossom now that they do not have to be "different" from other kids at school! Get that Christmas tree blazing away if that is what your family wants to do. It will certainly send the message loud and clear to anyone that might be wondering why you aren't at meetings anymore. Once they see that, you're probably toast as far as being DF'd but you do not have to participate in any way in their process. They will do whatever they choose with or without your presence at their little committee meeting, but you do not have to tell them ANYTHING, meet with them or answer any questions if you do not choose to. You already know what the outcome will likely be, so I would say just do what feels right for your family and to hell with whatever they may think of it.