I'd like to share a parallel story about my partner whom I suspect may have BPD. I'm sharing this just to showcase the severe reaction that non-BPD would otherwise let roll off their shoulders.

My partner was at work one day when I opted to take my girls shopping. It was a beautiful day but really cold and dad had the car. As it turned out, he finished work earlier than we expected. Since shopping is particularly hard for him, due to his medical condition, he can get quite impatient, cranky, and moody at the mall towards all of us. Days before, I had mentioned that next time, it was best I take the girls shopping without him because it was clear he was having a hard time managing.

Anyway, we didn't want to change our "girls day" shopping, nor were we planning on spending all day there. As it turned out, he felt completely rejected that we went ahead without him. As much as he understood my reasoning and stated it wasn't my fault, he couldn't let it go. He felt I didn't want to spend the day with him.. period. Days later he broke up with me because I wouldn't participate in an ongoing text marathon about his "feelings". He called me a narcissist and told his family we were done.. I wasn't meeting his needs. He eventually changed his mind. He claims he does NOT want a separation and doesn't want to give up on ME.

Extreme reaction? Yes. He already had plans with a friend that night and ended up spending a few hours out with his parents (he's really close with) while we were shopping.

Non-BPD may have been disappointed in my refusal to change our plans at the last second (we were already out of the house when we ran into him).. particularly knowing it was just circumstantial rather than a personal hit against him.

Do you see the parallel? He made this situation to be about him, his feelings, and his needs by putting me through the wringer about it. Bottom line is, he wasn't expecting this. He assumed we'd be thrilled he came home early.

My point being, your brother has been engaged for a DECADE (unless I misunderstood) so there was plenty of time to mentally prepare yourself for his wedding.