My husband and I have different last names. I did not change my last name when he and I were married because I had already published and didn't want to generate confusion. As time has passed, I've been happy with the decision for other reasons. For one, most students, staff, and other people at this university don't realize that he and I are married unless I tell them.
At family functions I don't mind that we are collectively referred to as "the Husband's Last Names" because we are a family and one last name makes sense. But at work I don't want that to happen.
At a departmental event, my department head called for me as "Dr. Husband's Last Name," when he knows that I'm actually "Dr. JP." I was so amazed at this step out of bounds that I answered and didn't correct him. Would he ever call my husband by my last name? I'm thinking, no.