Sims automatically perform certain romantic actions, even if they have a dislike for those actions. Because of this, relationship satisfaction drops very quickly. Example: A Sim automatically flirt...
Ideas
After some more digging, I believe something could be bugged with Lifestyles? I tried checking for hidden buffs on my Sims with MCCC and found that they have an underlying Romance lifestyle, despite me having Lifestyles turned off in the Game Settings. I know of another Sabotage! bug which could be related to the Technophobe lifestyle too. Hope this helps narrow the search.
no this is not caused by lifestyles. if you visted a community lot, you'll see everyone flirting, regardless if they are married or not
