Sims with Evil trait drive me NUTS

I'm going to suggest here that part of the originally stated problem is that only one sim or some subset of the household is Evil and there are ensuing personality clashes ruining the otherwise day to day harmony one might expect at home. My experience has been that two Evil sims can easily maintain a happy relationship and a house full of them get along with each other quite well especially if they are also Family Oriented or have other family-positive traits.

I have a household in one of my worlds where the single Dad is Good and two of his three teen kids are Evil twins (the other parent was never in the picture, I created these sims as a family unit and added them in ages ago). The Dad rules his house with a kind but iron fist. Of course teens will "act out" sometimes, but whether I am playing them or they are left to their own NRaas SP-controlled devices, you couldn't ask for a more stable and loyal family unit, and the teens' relationships with their also Evil steadies seem to be fine as well.

Now if they or some of this lot were Mean Spirited or Grumpy, or had other clashing and annoying traits like Diva, Socially Awkward, or No Sense of Humor, etc. then things might be a bit different. :)

Ah. I think you pegged it @igazor. My evil Sim was also a diva. Her husband had no sense of humor, was neurotic and dramatic. So basically their marriage didn't really stand a chance if left to their own devices. I will continue to randomize my Sims but will keep an eye on incompatible traits if I want happy families. I've never randomized like this and it sure has taught me a lot of things and let me see some crazy actions!