People with quiet BPD, how do you differ from normal BPD?

Most of the literature focuses on the more volatile, attacking, controlling type of BPD, but that's not my experience with my partner for instance. He's more like an avoidant BPD and he very rarely gets outbursts. In fact, I prefer when he does because then at least I have something to work with, but most of the time, he shuts down or creates distance and then comes back a while later as if nothing happened. He'll address the issue if I press him on it, but it clearly makes him feel ashamed and uncomfortable to talk about it.

People with quiet BPD - are you going through the same things internally as in normal BPD? How's your internal world? Do you let your partner see when you get triggered or are you also more comfortable in "hiding?"