I don't like other women sitting in my boyfriend's passenger seat.

Hehe, first of all, you are possessive, but cute. I think so too. That position should be reserved for my own woman.

But from the standpoint of that female colleague, she also has her difficulties. Because from the worship point of view, if someone gives you a ride, you must be in the passenger seat, which is polite. If you sit in the back row, it is impolite to treat others as drivers.

So your husband should talk to that woman face to face and tell everyone to stand down and say it politely.

I don't think your idea is too much, but unless your husband puts "dear seat" on the co-pilot, it is inevitable that others will grab your position.