It wasn't your decision, and honestly, maybe you should direct any questions or conversations about it to your brother from now on? Take yourself out of the middle of it?
Stella- Yup, you're absolutely right... I definitely should have told my brother that he needed to be the one to tell AH. I think that I decided that given the choice of having to deal with a tantrum from my brother about being told that or a tantrum from AH bc of my telling him he could not come, I picked dealing with AH.
Growing up I was the cause of all problems in my parent's marriage, my family, etc... (according to my mother and my siblings played along to keep themselves safe). My brother whose wedding it is still throws this kind of crap at me when I don't tolerate his passive aggressive behavior. I know he ought to have been the one to tell AH but I decided I didn't want to deal with the wrath from him if I told him that. I guess that's enabling in a way? But since I have to go to the wedding I didn't want to deal with my entire family being pissed off at me for "making brother x uncomfortable".
Not really the healthiest move on my part but it was kind of a 'choose the better of two evils' for the purposes of self preservation. I feel much better equipped to deal with AH's reaction than I do regarding my FOO.
I'm going to keep my therapist in business for life at this rate!