Missing audio block files has happened again on 2.2.2 PLEASE

I have windows 8.1, and Audacity 2.2.2. I have been working on my home recoding, which has hours and hours and hours of work, my audacity freezes up and closes program, and when I reopen Audacity alllll flatlines no more song. Can someone please help? Can I use ease us recovery, or the scariest is system recovery? Please help.