How to stop my Sim from doing autonomous mean interactions?

I have had this problem for quite a long time.  I noticed it several months ago and stopped playing for a while until recently. Then I remembered this bug and it seems worse now than it was before. I think it has to do with hidden/stuck negative sentiments. I tried everything and nothing worked. In one household the other sim was Evil but it happened in a separate save where nobody was mean or evil. It was because Father Winter flirted with my sim and was accused of cheating by their spouse. The sentiment went away but days later the autonomous mean behavior started between them and these are sims that are never mean to each other, and almost nothing bad ever happens in this household. Then I did a tester save with two new sims, had them go steady, had one cheat on the other and after the negative sentiment wore off,the mean behavior started again. So I think it is related to a lingering/stuck sentiment that we can't get rid of by typing in cheat commands (I tried!). If you're not opposed to mods I found a mod over at MTS called Easy Sentiments Cheats and it works for base game sentiments. As a last resort I tried this the other day and it worked. It got rid of the "invisible" grudges and now everything is back to normal. I don't think I can link it here but that's the name of the mod and where it can be found. Good Luck!