I wonder why your MC would recommend getting angry at your therapist over a diagnosis that's associated with emotional dysregulation? It seems like it would just make her feel more satisfied somehow. I'm not saying I wouldn't take issue with her assessment, but I would find a different way to do it, or find a different focus of therapy with her if you decide to continue. And if you feel there's some competition going on, maybe leave out references to your MC. Whatever you do, I'm wishing the best for you. This is hard stuff.