Butler leaves whithout being fired in the Sims 3: Showtime

I imagine this is a cumulative goal, not something that she has to do all at once. Just keep at it and it will eventually be granted.

Short of that, the fastest way I've found to make money outside of careers is by writing novels. Once you've mastered it, you can pump out a novel a day for an insane amount of royalties.

The Sims 3 is notorious for high CPU and resource usage, especially when you get multiple households and things going. Try opening up the task manage (ctrl+shift+esc) while playing and take a look at the CPU and Memory percentages. If they are pegged at 100% or close to it, that may be the problem.

The game does try to "optimize" by instead of the entire game chugging, only certain processes of it do, like sim behavior and the background world simulation (which is why everyone is tired). Something to try is lower the various settings, or removing households you don't really care about so the background simulation doesn't have to work as hard(backup your save in case this doesn't work!).