We suffer from quiet BPD and lashing out in anger is not something that usually happens. In fact, it's a very rare thing to see us get seriously angry. However, we do feel like there's always a sense of bubbling rage under everything that builds up constantly, even when we're having a good time. Even if we do get angry once in a while, this anger doesn't ever go away. It just kind of sits there and it's super frustrating for us because we can't let it out. It can make us feel irritable, unhappy, or uneasy. 

Could this be because of borderline or would it apply more to an alter in our system (we have OSDD)? Or is it a trauma response?