Sorry for your trouble. The leading cause of this problem are faulty or outdated drivers for your video display card (GPU). Check out your System Preferences and see if CUDA needs updating. Also, check out your System Preferences > Energy Saver and make sure Automatic Graphics Switching is set to off.
I am Windows, but I do have a few saved Mac discussions... these MAY help
Mac Retina Bug http://forums.adobe.com/thread/1159632
Troubleshooting guide for Mac freeze http://helpx.adobe.com/x-productkb/global/troubleshoot-system-errors-freezes-mac.html
Thanks for the replies Kevin and John. I re-installed premiere to clear any corrupted files from the plethora of crashing and then updated my CUDA drivers via the system preferences and it seems to be working smoothly now.
I still had a couple freezes today, but they seemed somewhat more benign as I was copying sequences imported from CS6 in to sequences of a different framerate, which is probably a bit more awkward to process.
At any rate, it's not experiencing fatal errors every two minutes, so thanks again for the help!
I have the latest CUDA drivers (6.0.46 and GPU driver 8.26.21) and I have checked my energy saving settings to make sure automatic is disabled. But I'm still having this issue. Premiere CC 2014 simply crashes on startup and says no suitable video driver.