There are tax relief companies that, for a fee, will negotiate a settlement with the IRS if you are in financial trouble and it sounds like you are. There are scammers among them, but some are legitimate: your husband would need to look at consumer reviews and check with the Better Business Bureau. But it is possible.

There is obviously a huge power imbalance in the marriage, and one symptom of it is that your husband is hiding from you how much you owe to the IRS. But you said that you saw letters that come from the IRS. Have you ever opened them or is your husband now allowing you to open your joint mail?