hey sweetie! if you really want to lose the weight, i think that you will be able to find the willpower to do it.. Kimberly is right - there are tons of lower calorie, lower fat alternatives out there - and even really great recipies for at home... i recently discovered this brand called "no pudge" - I'm not sure if they will have them in england (i'm guessing b/c of the 'stone') BUT basically they use yogurt as a substitue for all the wet ingredients...
Also remember that portion control is key... instead of having a large slice of cake, eat half of it. Take fewer cookies... if you try to tell yourself that you can't ever have it, you will end up slipping and won't be able to stick with it - so indulge... just not all the time, or as nearly as much as you might have before! =)