The cost of housekeeping services are never a deductible medical expense; only personal care services may be deductible under certain conditions. However, the cost of housekeeping services incurred to enable you to work may qualify for a dependent care tax credit. To be eligible for this credit, the nonworking spouse must be physically or mentally incapable of self-care. Whether your wife meets this condition is up to your doctor.
Generally, an unmarried person who maintains a household for dependents and is allowed to compute his or her tax based on head of household rates, which are more favorable than single person rates.