Ethel is right up to a point. If the debt can be paid by insurance or from any assets your husband left (after his funeral expenses have been paid), then it must be.
However, creditors cannot get blood out of a stone. If you have no assets & are on Income Support then you should not be expected to pay more than �1 per month off the debt, and any interest and charges should be frozen. If necessary, get help with this from your local CAB but do not get involved with any commercial debt management company.