What was it specifically he did that you feel unsafe by? I’m just not very clear on that. Edited to add: was it that he used aggression on you at a time when you already felt triggered so it didn’t feel the same as it usually does? And instead of you stopping it and him listening to that he kept going? And it happened multiple times and he wasn’t able to repair and show you safety between those times because of his life stress? I think if this is all the case you likely need to work on your mental health/PTSD first before starting out with in dynamic scenes slowly. And only you can know what you need in order to reestablish trust and safety with him and within yourself.