I'm going to parrot others that his being dishonest / not forthcoming is the bigger issue.
Poor money habits on behalf of one partner can be fixed easily. As someone else mentioned, a proportional split of bills is fair, it shouldn't be 50/50 if income isn't 50/50.
From there there are a couple of options:
yours/mine/ours accounts. You decide what your reoccuring monthly bills are and how much each person needs from each paycheck to go to the "ours" account. ONLY household/joint bills/expenses are handled from that account.
He hands over x dollars a month for his share of everything. You take care of all bills/joint expenses.
He hands over his entire paycheck and gets an "allowance". Very similar to the above two. Works with his/mine/ours. You each get an allowance to your own account with everything else sitting in "ours".
You MUST have regular budget meetings though. And not long, drawn out affairs. This week we need to do xyz. This week is tight so beaware. ETc.
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