Mom upset I broke up with ex

I need advice. Or to vent. Or both. I mutually broke it off with my boyfriend of a year and a half recently. We both came to the conclusion that we only see each other as friends and it was just weird to date, but we're still good friends. My family, however, was enamored with him, and my mom is...not taking the news well. She doesn't understand why would break up if we're friends ("You're supposed to be friends with the person you date, though?"). She's refusing to accept that we broke up and stated that they "won't accept anyone else" into the family.

I already have a....tense relationship with my mom, but this is especially irritating because it isn't even her relationship.

Is there anything I can do here to get her to stop....well, pouting?

Edit: to clarify why I'm even bothering trying to talk her down from pouting, I currently have to live with her due to the pandemic 🙃