Its hard when it reaches that point. I'm sorry, it sounds like youre in an awfully abusive situation. Abusers will frequently take advantage of that, and it can be hard to regain agency when it feels like you cant even communicate at all. If you ever get the opportunity? I would leave as soon as you can.
Grounding excercises are a theraputic tool for tackling dissociation but can also be useful for those with anxiety and PTSD. Theres a lot of different ones, but they are meant to help the person become more grounded and present in their surroundings, with the goal of easing symptoms. Given from what you told me about your situation I wouldnt reccomend trying those sorts of things till youre away from your partner, but if youre interested in looking into them they might be of some use.