Have an aunt who has only ever lived with women. I was always told it was her roommate. Everyone refers to her as a roommate. They BOUGHT THE HOUSE TOGETHER. Have dogs together. Raise the other ones kids together.
When I was like 17, and openly gay, I straight up asked my grandmother if her sister was a lesbian. She said no they're just roommates and got super specific about it. I asked my aunt a couple weeks later when I saw her and she went "Well, yeah. Do I not wear enough flannel?"
This is a good anecdote about misinformation as well - when someone believes that they have the answer, they often never reassess the situation, which can get to the point where the real answer is staring them right in the face, but they can't see it because they're not looking; why would they? They already know the answer! This is how lies can spread so easily even when easily debunked. Nobody bothers to listen to the debunking.