Last Invite Addressee Q for now....

My aunt is widowed, but still wears her wedding band and is totally still devoted to my uncle.

Would I address the envelope as

Mrs. Uncle's First Name Last name?

or

Mrs. Aunt's First Name Last Name

or

Ms. Aunt's Name Last Name?

Thx.

I'm doing up my invite list for the printer

I had an aunt in same situation, I addressed it

Mrs. Aunt First Name Last Name

Mrs. Aunt'sfirstname Lastname