As someone who has given up smoking after smoking for 13 years let me tell you something. People who make fun of other who struggle to give up fatty, sugary junk foods really need to think again. I honestly believe that giving up on a bad diet can be one of the hardest addictions in modern life. Junk food is not only cheap, it is readily available and it seems to be everywhere these days. I cannot speak for where everyone else is from but i do know from living in the UK and travelling to the US, Canada and Europe many times that Junk food is not only readily available but sometimes it is the only option available! Often if you are hungry and in shopping centres or supermarkets the places to eat tend to veer towards junk foods. I suppose it also depends on how you would categorize 'junk' foods? There is, of course, the obvious options such as Mc Donalds, KFC etc but i would also consider most of the pre made sandwiches, sub rolls and other convenience foods that we tend to eat on the go as they will invariably be high salt, high sugar processed foods. In some ways these are the most dangerous because when you go to McDonalds, for the most part, you realise that if you go all the time and buy a supersized Big Mac meal or whatever you are going to put on weight. When you go to a supermarket or a cafe and pick up a sandwich you wouldn't necessarily give it that much thought though and sometimes these items can be the ones that do the most damage as we'd tend to eat them more regularly.
So how to try to break the habit of eating junk foods too much? Well, i believe that with many things in life it is all about momentum, you've got to start and try not to stop but be realistic....start by cutting back. Say you're only going to have something once or twice a week, try it for a few weeks and then try only having something once a week. The absolute biggest hurdle for any dieter and, in my opinion, the main reason crash diets are either totally unsuccessful or work short term only for the dieter to put back on weight is that people need to make their diets Realistic and sustainable. Don't go from eating big mac and fries 5 days a week to eating lettuce leaves and carrot sticks every day it just wont work long term. try having a homemade burger and drop the bun with some oven baked fries for example, replace your favourite foods with healthier alternatives and commit to having a portion of vegetables or two with each meal. Eat the veggies first so your partially full then eat the rest and when you are full just stop eating. Society has taught us this (if you think about it) weird habit that we need to try to eat every last morsel on the plate but why? eat until you are not hungry anymore and then stop. Pretty soon, rather than waste food you will start dishing up smaller portions.
Another piece of advice i would offer is one i used when i stopped eating animal products. Stop thinking about what you cant have and find new things that you can look forward to and then eating wont seem like such a chore. If your constantly comparing your salad to a big mac you probably wont enjoy it. Find things you love to eat which are healthy, read recipes online, cook for yourself and forget about the old stuff. You really don't need it, it's all in your head!
Good Luck!