Sims with the Loyal Trait keep breaking their loyalty

Many of my sims have the loyalty trait so they won't autonomously flirt with other sims. After the last update before this update, when sims came over they were happy at first, but after interacting with a sim that wasn't their partner, even with just a friendly interaction, they would immediately get the very tense cheating moodlet. I love having my sims interact with each other, but now even with the trait, they are near constantly just flirting with each other. (I do apologise if this has already been brought up. I just can't enjoy it with having to fix their relationships constantly.)