Not picked as a bridesmaid

That was incredibly rude of her. That was inappropriate and just straight mean to have you stay and not invite you. I would be similarly upset and likely would not make much of an effort in the relationship but not necessarily make a deal out of it either. Sounds like a friendship ender in my opinion.

That was so unbelievably rude and cruel of her! I cannot even wrap my head around this insensitivity! Inviting you and then insisting you stay... to be excluded??! This feels intentional. There's no way someone doesn't realize how wrong what they're doing is.

I am so sorry you were subjected to that horrendous behavior!

Awful! No, you're not overreacting. She was incredibly insensitive and inconsiderate. She's offensive or clueless to the point that I would tell her that you felt hurt, not because you weren't asked, but because of the tone deaf, jerky way she handled this. Her reaction would determine what I'd ultimately do about it, but unless there were extenuating circumstances, I'd be seeing her and the friendship differently.

The only thing I notice is that it wasn't the bride-to-be who begged you to stay, it was one of the BMs. Is it at all possible that she intended to give out the bags after you'd gone home? Of course, that begs the question of how she could know you'd leave first, unless the others had a head up or something. For example, she told only those getting boxes to stay after dinner for some kind of surprise. Could that be why the other BM wanted you to stay so badly? Regardless, the whole thing was in really, really poor taste. And in the unlikely event this is what happened, the bride should have canceled the plan there and then.

I read it as the one that wanted her stay is the one that handed out the proposal bags (the bride to be).

The future bride to be is terribly rude. She's not a friend OP.

You're right. I read "one of the girls insisted," thinking it was one of the other women but it was the same person, ie the bride. Sorry!