Dear Focused:
Jo is so right; focus on one day at a time, and look around here every day.
I find just reading about others' struggles and successes helps me in some way. Like you, the Christmas season was sabotaging, but then I re-focused on my main goal which is sustainable, long-term health.
For me, managing my emotions is key. So, when I'm upset now, I just come here, instead of to the fridge or cupboards. I found banishing all the junk food out of my house one of the biggest helps; and next year, during the Christmas season, I am making some new healthy and permanent changes to our way of celebrating life.
Maybe start with 10 lb increments (3 x 10 lbs), which may not seem so daunting for you, right now. Just hang in there ~ a fellow encourager ... Rosebud.