OMG! The utter AUDACITY of them to show up even after you specifically asked them not to. Its one thing to show up unannounced, it's a whole other level of disrespect to show up when asked NOT to.
I am sorry that happened ER, for them to do that to you during this period of huge adjustment for you is unbelievable. You certainly did not not the added stress. I think I have only read of one other story on these boards of family members acting so egregiously during the time of a new baby. People blow my mind. Even before I had a clear understanding of boundaries I would have never shown up anywhere I was asked not to. Who the heck does that???
I am sure he thought he'd show up and "trample" all over your boundary and get away with it because he has in the past "gotten away with it". Well you showed him! Good for you and your husband. If this brother is the one sibling in your family you considered the healthiest most reasonable one, then I think you are making the most correct decision to stay no contact with your family. If he is the "good" one...yikes!
You got a glimpse of what it would be like to be re-entwined with the enmeshed horde and you said " no thanks!" (To put it politely.. because I would have probably used a different phrase...)
I hate to say you can "thank" your brother for this gift of clarity, but you can take it as a silver lining to a crappy situation.
Keep flexing those boundary muscles, they get stronger with use and it's an amazing feeling when you realize you don't have to think about them anymore, you just live that way and it feels so damn good.
When we know better, we do better. You are doing great!
Thank you for sharing this with us. I'm still kinda gob smacked they showed up!!!!