I had the same issue. Very frustrating! I tracked it down to an issue with fonts. In particular, I found that it was something to do with Suitcase Fusion and possibly that some of my fonts had got corrupted. I did a big cleanup using FontDoctor and, reactivated FontBook alongside occaissionaly using Suitcase Fusion. All is OK now. I lost 3 days work and a couple of days to put it all right. A week in total. So much for software improving productivity!
Come on Adobe, pull your finger out. Life is too short!