You are at that stage / impasse where he refuses to agree with you over the situation. Nothing else will happen now.
Words, pleas, your begging, frustration, trauma are having zero impact. Well actually they are - he is locking down his ‘privacy’ and doubling down on his delusional claims.
All of this is just cutting deeper and hurting you more.
Actions are your next step.
You do have agency. His behaviour isn't acceptable to anyone. You don’t have to blow up your life today or dive in the deep end but you do need to take some steps for your own MH and financial future.
Have you spoken to a close trusted friend or family member IRL? And / or can you or are you looking for online support via groups / info or face to face with a therapist? Do you understand how a divorce process works - it might be good for you to so some research so that you know the timescales / implications etc.
Are you still physically intimate or has this pattern changed over the past year?
I would retreat from your DH emotionally and take care of yourself and protect yourself emotionally. He is knowingly hurting you and doesn’t care for you.
You need to take yourself out of emotional punching distance.