So he hid your means of communicating with the outside world. There are no good reasons for doing that.
You feel sick and anxious because you know that you are in danger and you need to get yourself safe. NOW. Please understand it is not normal to feel sick and anxious round a partner, even a partner who is angry with you. Sometimes I p* my DP off mightily (as he does me) and we occasionally have huge rows. I never feel sick and anxious around him because I know I am safe.
Given the urgency of the situation, getting safe probably involves you leaving rather than him (if necessary, you can apply for an occupation order after you have left and if it is granted he will need to leave the house and you will be able to return there).
It really isn't clear what is keeping you with him – you haven't mentioned DCs or pets - though they would also be happier away from him, no doubt. Perhaps it is the thought of the years you have wasted with this man. But you know – we all have things we would do differently if we could turn back time. We can't get that time back. What you can do is make sure you don't waste any more of your life with him on the basis of how many years you have already spent with him (google "sunk cost fallacy" and you'll get the point).
It's clear from your posts that you have been beaten down and are probably somewhat traumatized - you can cry once you are out - but right now you need to act. If you don't have friends or family you can go to immediately, then take yourself to a B&B or a hotel. Just get yourself somewhere he is not. You mention he's still in the house. Keep secret from him that you're planning an escape. He may become more dangerous if you tell him you are leaving. Just grab your handbag, pack a few comfort things if you feel safe to do so and walk out the front door. Also keep your phone near and if he threatens you, ring 999. Immediately.
As regards not having many friends to help: you only need one and indeed you can manage this on your own if you have to and work on increasing your friendship circle once this is behind you.
Are you out of contact with your family because he has isolated you? If so, they may be delighted to help you if you reach out to them.