Up until just a few hours ago actually I would have told them just exactly how I felt and let the cards fall where they may.....
But the new Beth is taking the same approach as you, if you can't say anything nice, don't say it at all. Or just ignore whichever is best for the situation. But I'm talking about online things...if this is someone you know if real life then I think I would try to talk to them about how you feel. It would depend on what they did also.
Good luck whatever you decide.