Oh weekends. If we didn't have weekends I'd probably be down 120 lbs by now!

They're for relaxing and they break up routine, so of course they break up my weightloss routine! *sigh*
However, while I'm still working out the weekend kinks myself, I've found that planning my dinners for the weekends on Friday has helped. That way if I want to eat out, it's planned. If I want a nice wholesome meal at home, it's planned. If I want to eat a bag of chips, planned!
They might always be a trial, but with time & practice weekends will become easier.