Illustrator - Data Loss and Crash

Hi, I'm writting stunned- but hopeful to resolve this issue. Yesterday my illustator crushed, without any reason.. and files that I've been working all this week- are gone, even though the were all saved in creative cloud. Is definitely unacceptable to be real. So there has to be a way to restore it, even if it seems evaporated. Otherwise I'm afraid to put my time into another project. Please help. Thanks