This is such an awful situation to be in. It's cruel, really cruel and controlling.
I think you should have a chat with your GP regarding your symptoms of anxiety and what you can do. Personally, (and I have said this on other threads), I would recommend you learn meditation or mindfulness...there are courses everywhere these days and these practices can really help in dealing with anxiety and negative emotions.
Decluttering and getting yourself organised is an excellent idea...really constructive action and will help you feel more in control of your situation.
Depending on what your DH is like when he is not ignoring you, you may want to try relationship counselling...you don't have to go as a couple, you can go on your own....it can help you look at your options and may help you see things in a clearer light. You don't have to tell him what you are doing.
One thing for sure is you don't have to put up with this. Start to carve out a life for yourself....find an evening class to do, go out with a friend for coffee, go for walks. Remove yourself from the toxic environment and get out more. It will help you gain perspective.
Try not to show him that you are upset or anxious by his behaviour. Instead, if you can, be joyful. Smile, hum tunes to yourself, keep busy, go out...do not let his behaviour control you. Take your power back and take control yourself.
I am so sorry this is happening to you. You will get through this but you will need support so start building that support network if you can 