Is it normal to fantasize about your partner with someone else?
Yes, it’s normal to have this kind of fantasy, and it doesn’t automatically mean you want your partner to be with someone else in real life. Fantasies can be exciting precisely because they’re imagined, not plans or requests.
People’s fantasies can include all kinds of scenarios, including ones they’d never want to act out. Imagining your partner with someone else might connect to curiosity, novelty, jealousy, or simply a story your brain finds compelling; it doesn’t prove anything is wrong with your relationship.
You don’t have to share the fantasy unless you want to. If you do, talk about it as a fantasy rather than an expectation, and make sure you’re both comfortable before turning it into anything real. It’s also fine if one of you finds the idea exciting and the other doesn’t—fantasies don’t need a committee vote.