Holy moly Emily. Please locate some cash, and use it to speak to a lawyer. KNOWING what your out situation really might be, would be great therapy. He will if he is anything like mine, he thinks that everyone has a price. Right now he is acting as if he owns you. Lawyer up. Assume he has all the usual on your phone and leave it at home, make paper notes. Could you buy a PAYG for typing here etc? Knowing you are clawing back some control helps.
You don't need to act on it, I am not trying to bully you into leaving, but knowing helps. You might decide to laugh at his satin clad repellent ass, if it nets you X per year and you fancy a nice retirement away, once the kids are grown. Or you might discover that despite his threats, you will be OK.
This isn't your secret to keep. If he insists on living this way, let him explain himself to the kids and family once you have gone. You could be very Nicole Kidman about it, dignity is attractive. Let this foolish man make a fool of himself. If you weren't there "as an anchor" what would he do? And would this prove you correct and not crazy?
Take photos. Not to hurt him with, photos of his stuff if not of him. Document this binge, what he says, because next time he is on a martyr purge, he will try to minimise your experience, make you question your memory. If you document you will know, really know, that it is him and not you whose grasp on reality is questionable.
And if you can find a way of stopping this being on your mind all the time, if you can sleep through the night, please tell me how!