Am I responsible for my husband’s debt after he has passed?

Maybe...

Will My Loan Be Cancelled If I Die?

“If you have federal government loans, yes. This means that your estate will not have to pay back those student loans. Survivors can apply for a death discharge to cancel a borrower’s federal student loans.“

“There is no administrative discharge for private student loans if you die. Private loan debts will be handled the same way as other debts. That means that they will be part of your estate. This estate settlement process (also called probate) varies by state. Some private lenders will use their discretion and agree to discharge loans when a borrower or co-borrower dies.“

This is from https://www.studentloanborrowerassistance.org/will-my-student-loan-be-discharged-if-i-die/

Google Federal Student Loan; if this happened to be a Federal Student Loan, according to the government site, it is cancelled with the death of the person involved. You now have three different opinions, so my best advice to you is to run this by a lawyer. Where things like legality and money are concerned that is almost always your best bet. Generally there will be a legal counsel involved even if on the periphery in any death and filing of probate, Trusts, et al.

According to Nolo, if you live in a community property state, you can be held responsible for his debt.

No.  If he has an estate, they can look to the estate, but not you