hi frenchy,i know all about craving nutella, i like it a lot, too.
however, i doubt you're really addicted to it in the sense that you get withrawal syptoms once you eat less or none. so there's hope, hon. 
one can change eating habits, and eating healthier doesn't mean completely getting rid of nutella, or choclate in general altogether: just have it in moderation.
how about spreading it thinner for a start? it's very strong flavoured, so a little can go a long way.
also, how about swapping the white toast (if that's what you're having it on) for a healthier bread variety.
if you really want to go cold turkey (which rarely works, in my experience) don't have it in the house (if you don't do the shopping, ask your mom to not get it) - and now matter what, make an effort to have healthy alternatives in reach instead. - for every nutella toast you have, how about having 2 extra servings of fruit or veges?
my best galpal likes nutella so much she scoops it with a spoon sometimes, and only buying the smallest nutella jar available has helped her in recognizing earlier when she's head enough.
if i find i crave choc (and that's perfectly okay, anyway!), what works for me is to have a little bit of very rich, i.e. 85% choc or a cup of hot cocoa (low sugar, prepared with low fat milk = extra calcium! yay!) instead of a lot of nutella toasts.
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Caro
~Scarleteen Sexpert~
Spike: (In response to being asked to fight a troll) "I would, but I'm paralyzed with not caring very much."