I can at times feel no interest in running the game, but because I also run my own "game" on my blog/website, with tons of detailed background info, there is always something for me to do without really playing. I probably play the game only half the time I focus on my sims. So, I think it's healthy taking a break from the game and do something totally different, or do some planning or cleaning up in the Screenshots folder, etc. When ding something else, you will probably find new inspiration :)