Yes, as a medical expense which would be listed on Schedule A if you Itemized Deductions.
If you take the Standard Deduction, the expense won't matter.
TurboTax will tell you which is more advantageous, the Standard Deduction or Itemizing once you finish entering them.
Enter the miles driven in the Medical interview under Deductions & Credits.
To be clear, the miles I drove (90 miles round trip) to visit my husband for 7 months during HIS hospitalization are deductible under the medical mileage?
Certainly the trip to and from the hospital when your husband made the journey would be deductible as a medical expense. Your visits to see him would not qualify as a medical expense because you did not make the trip for a medical purpose.
There are some examples given in IRS Publication 502 that explain when transportation (mileage) expenses are deductible. The only example where visits by someone other than the patient could be deducted is for the case when regular visits are made to see a mentally ill dependent when the visits are recommended as part of the treatment.