I have a neighbor who is very controlling of her husband. She is kind of upset that he went to a strip club before they ever met. She brags about him being a virgin when they did finally get together. (She had kids from a previous marriage.)
So once the topic of guys looking at porn came up, she (not surprisingly) said, "Why should he look at porn when he has me to look at?" I tried to talk to her about the different ways of seeing this. I suggested the "one free celebrity" type game where you can name a famous person your partner gives you permission to be with.
I once wrote a column for my local paper on polyamory which reopened the discussion. She did kind of realize that she is being controlling of his time and is acting a little insecure. But not enough for her to change her opinions.