I was in management consulting over 10 years ago; it was my first job out of college and I loved it in the beginning. In the last year of my consulting career, I felt burnt out and wanted out, so I started to slack off a bit and focused on business school applications. I know how you feel, especially your company sounded cut throat. Take a break and get some rest; you can always apply to good corporate roles that are not nearly as demanding with better pay and company culture.