Game Closing Unexpectedly

I can't tell you how long this has been going on for but it was even before the most recent update. My game will randomly close, without warning, every so often. It's getting more and more frequent. Nothing in particular seems to trigger it, it will just happen and I will lose everything. I am now having to save every 2 seconds because I never know when it is going to happen. I play on Mac, game is up to date, I have not done the latest Mac update so I have no idea if that is why it's happening but it shouldn't be. I have all major packs apart from a few kits and stuff packs.