Well, I am (was?) a total chocolate addict. Sam drank a lot of coke/other sugar drinks. Two things helped me not have a bit of chocolate for two weeks... first of all, whenever you think about the stuff you're not allowed to have, think of all the stuff you are allowed to have.. looking at LC recipes helps.. make yourself something really really good that's totally allowed. That always makes me think 'diet? WHAT diet? look at the great food i'm eating!'. The other thing.. when everyone says that after a week or so you'll stop wanting the sugary foods so much.. it's true. You might still want it, but it's more 'I wish I had some extra money to buy myself nice things' than 'NEED money NOW to pay rent or will be evicted and thrown out into the street'.. hope that analogy makes sense. Will power is the most important thing.. remind yourself why you decided to go on the diet and give up sugar in the first place.
Good luck.