Hi hun, I am exactly the same. I think "Oh I'll get back on it tomorrow" or "its the weekend" or "I'm going out for dinner" and blow it, its crap and I feel awful afterwards. I'm joining a gym this weekend and I'm going to try (haha) to go in the mornings twice a week, like you said keeps you on track all day.
With me its all or nothing.I know the healthy attitude to have it "OK so I had crisps, now I'll be good and go to gym to work it off and have a light dinner" but I don't, I think, "Right I've blown it now I'm having more crisps, toast, bread and butter, chips, everything, and there's no point going to the gym 'cos it won't burn half of this off. I've done it for years and years, yo-yo dieting and bingeing and its not healthy but I honestly think I am addicted to food sometimes. I stuff it in my mouth quickly and barely taste it, love eating on my own, and just get as much in as I can.
It's a really unhealthy attitude to have and I'm really going to try now to get back into it and get this weight off. You're not on your own and YOU CAN DO IT you just need to get into a cycle of a few weeks, once you're into it you'll probably stick to it better.
Please don't give up, allow yourself your syns and eat them SLOWLY. Dieting isn't fun, even a diet like this where it's pretty easy. But being overweight isn't fun either. If it was an ideal world we'd all be slim without trying, but then wouldn't we all like to be rich without working. I really wish you all the best in this, please keep coming on here for support because I know so much how you feel and if you ever want to chat just let me know.
Sorry for the long rambling post but it's just like reading my own mind! x x x x x x x all the best