There's a few game glitches like this that display such messages when they really pertain to other random sims around town. In addition to the one this thread was about, I keep getting "The Experiment was a success (or failure)," "Operation Failed because one of the sims is a teenager," I think I even saw "No one came to your party!" once (what party? where? huh?) and other goofy stuff that couldn't possibly pertain to any of the sims I am playing. The group/romance one is a little different because it involves an intervention by way of choosing one of the options to dismiss, so it does feel like it appears more than some of the others. I usually just answer randomly, unless it's clear that it really is pertaining to my active sims. :)
