DW
I have been where you are. I know it is very overwhelming. You have to start somewhere however. Sometimes that might just mean one little thing, not one little thing with every issue you have.
It sounds like your AH is scamming some money out of the paychecks/expense checks etc. My AH has done the same thing. Had expense checks sent to him on paper so he could cash it without me knowing.
I know his paycheck pays the bills but if you really want to protect yourself you need to start removing your name or his name from any joint accounts or credit cards. If he is cash advancing on CC in your name YOU are liable for that no matter what. My AH's check was direct deposited into my personal acct and I paid the bills. It sucked in that if my AH wanted money he asked me for it. But on the other hand, I protected myself. I have no CC's jointly, accounts or the mortgage.
You need to check your credit report so you know exactly how much debt you are in and what is his/yours/ or joint. That way you can form a plan. If nothing else, open your own account and save your money in there, don't tell him you have it.
You need to understand that unless you take precautions things will most likely get worse. I know you feel buried but you just do the best you can and it will have to be good enough. I've been in exactly the same position so I do understand. One step at a time, get some face to face help from others who deal with these situations (alanon or whatever). You may find a network of friends that can give you good advice or avenues to pursue.