How to get work done on the weekends
One solution that has often worked for me is to try to not work on the weekends.  If your weekdays are solid work times, then you can do more intense work on the weekdays and aim to have your weekend entirely free.  Even if you don't entirely succeed, you'll still be in a much better situation with respect to the things you need to do by Monday.  Then you can take real time off and have fun without guilt and actually recharge yourself for another solid week.