I do know what stockholm syndrome is and I can understand why you would see that in Emma, but never in ashley. Ashley is stubborn and easily hurt, there's no way i can plausibly see her just making up with the twins in a single shared holiday. She's pretty jealous pretty long in the game (i can't recall if she is actually wary of the twins later on but as far as i remember, she just becomes friends with them), which amplifies that she doesn't just easily share. So I fail to see how shit hitting the fan both directions would make anything up to any party there, rather amplify their animosities..