I don't think that women are too dumb to separate fiction and real life, as the moral panics around romance novels would have you believe, but I do think... it's complicated. I think sometimes small, insidious things can embed themselves in your consciousness and your idea of what a "normal" or healthy relationship looks like. I think it can happen to men too, the regular trope where the action hero is basically handed a girl at the end of the movie, almost like a reward for his achievement. We all know it's a silly trope, and yet don't we see that idea in our culture? That if a man is worthy enough and has achieved enough, he deserves a human female as a reward. Some people certainly seem to think so.
Take the idea that healthy couples must sleep in the same bed, which I hope can be less controversial than some other examples I might use. There are many medical or personal reasons to sleep in different beds or even different rooms. There are many healthy marriages that don't involve cuddling all night. Many people cannot sleep while touching another person! And yet this idea of a couple sleeping in each other's arms as the height of Romance Achievement is very widespread. It's in romcoms and sitcoms and real life. It becomes an ideal. And perhaps it makes a real couple feel that they are wrong in some way for needing to go against the imagined norm. We just don't see how that many married couples sleep in real life, fiction is our primary source of data and it's very skewed.
People can separate fiction from real life, but we also can't. We build our idea of what the world is like from both what we witness in real life and what we read and watch, because we simply cannot witness everything ourselves. We use stories to teach morals and incite rebellion, that wouldn't work if our minds did not let the fictional and real touch. We build incorrect ideas about the past, about war, about love and relationships, about everything, and we also must learn to question those ideas and assumptions.
The solution, of course, is to learn critical thinking. The solution is to examine assumptions, not to ban some type of fiction in a moral panic. The key, I think, is to see that any story can create false expectations, not just romance novels on poor impressionable females, but any genre and to any gender. Fiction can be propaganda. It can create false beliefs. We create false beliefs all the time. That's what it's like to be human.