Hi Ianima. Welcome!
I don't really know what to offer. I don't have experience with this. My BPD relationship is my mother, and my H and I work as a team. If I was co-dependent with my mother, it would be difficult for my H, and it sounds like that may be where you are at, except the relationship is with your adult child.
When they scream, I stay calm and tell them we'll talk when things have calmed down and then I walk away — but my spouse tells me I’m partly to blame for the insults she hurls at me as I'm walking away, because leaving the escalated situation also triggers her. However, we had all previously agreed to this approach whenever things get too escalated... I've seen our daughter talk so rudely, attack her, blame her, and she just takes it. I need ways to make boundaries work when not everyone in the household supports them.
What strikes me first is that your spouse blames you for leaving the situation, but this is YOUR boundary. Someone else shouldn't dictate your boundary. It doesn't work like that. Also, your spouse is blaming you. That kind of Karpman triangle dynamic isn't helpful. It seems like your spouse may be acting as rescuer to the adult child (victim) and making you the persecutor.
You are entitled to your boundary because this is what make YOU feel safe in the situation. Personally, I don't think this is negotiable. That sounds like a conversation that is needed between you and your spouse, but I am not a counsellor or any other kind of expert. Just the daughter of a uBPD mother.
What do you do when one parent enforces boundaries and the other doesn’t?This is difficult. I don't have a suggestion. I can't imagine what it would be like for my H if my H and I weren't a team. I only want to offer support to you. Do you see a counsellor/therapist?
