Saturday+Sunday = 48 hours which you can spend without any obsessive thoughts about work. It doesn't mean you need to abstract from one but limit it as severely as you can.
We strongly believe that entrepreneur should work daily because this is more lifestyle than work, but... Never be like a robot and let yourself enjoying life and forget for some time about everything difficult/important/annoying and so on. You have 120 hours per week to think about it. WEEK is ENDing and we all must gain strength for the next.