ChloeJane, I actually think you are right about the value judgements that have been levelled against you... to be honest the original post did come across as overly controlled and I think that most people with a long-ish history of doing this sort of thing have learned that rigid boundaries from the start actually do harm more than help.
You sound very much like me, and I deeply respect someone who values integrity and honesty in themselves and their partners.
I have no opinion about whether rigid boundaries are a good idea or not... but aside from value judgements you do have an additional piece of information, namely that it isn't actually working for the other members of this group. The thing about boundaries is that things can and often do just go right ahead and develop as they want to. Your husband broke the rules and that's wrong. Now, like you said, you have to decide what to do with that...?