Ah you poor soul, you do sound down about this.
You're in the right place though! There's all sorts here - relative lightweights who just want to shed that last few pounds, those whose main aim is to eat a healthier diet, and those who need to lose several stones (count me in!).
Is it possible that you've approached this from a diet perspective too much before? What I mean is that it sounds like there are some fundamental lifestyley type things which might help you keep it off - slow weight loss being the most helpful way of keeping your weight off. What have you tried, what do you find easy, what do you find hard, what sort of exercise do you like and why do you eat - these things might help us make some suggestions, if you would like us to
A lot of us are using this website which helps to keep track of calories in (food) and calories out (exercise). As a long-time overweight person I always shied away from calorie counting but I've actually found it to be a really helpful guide after the first few days - and it gives you graphs and bar charts!
I am sorry you are so sad about this but we will help you along the way - this thread has been a great source of support and encouragement (and the odd kick up the arse). A warm welcome