Exactly.

There are some exceptions of course re being a confidant.

My husband has an old female friend, classmate from nursing school from years back before me and him met. They remain friends. She is married as well. When my mom was dying, she was on the phone with me helping with great advice (she is in a different branch of nursing than my hubs). We see them periodically, are going to visit them this summer as they live across the state etc Last time my husband went to visit them I didn’t go because I couldn’t get off work, he went to take something to them that her husband could use and we didn’t want in our house. I certainly am not jealous. So if she calls to talk once in a blue moon, I can’t care less if my husband talks to her or what about. They talk about their jobs usually that can get boring. They also ask each other professional advice. She is his friend, not mine, but I know her and her husband. There is nothing secretive or romantic there whatsoever. .

I think these type of scenarios are different from going to some random coworkers house. OP hasn’t met this person. Doesn’t know her. They aren’t old trusted friends. Personally if he considers this girl close friend or whatnot, I’d expect to meet her and I’d expect we both went to her house to help her out if she needed something. I’d not appreciate this secrecy.