Write down all the reasons you joined SW in the first place. Fish out some really unflattering photgraphs and remind yourself of how far you've come. Do you have a hobby you like? If so, spend some time on that. I took up knitting when I first started - I'm a rubbish knitter but it gave me something to do with my hands that wasn't eating! Think of low syn treats you can have that you really like and makes you feel like you are treating yourself. One thing I do when I want a drink is have slimline tonic in a tall glass with lots of ice and slices of lemon and lime - I can nearly forget it doesn't have gin in it! And even if you do have a gin and tonic, it's only four syns.
I hope your day is better tomorrow!