When it comes to weight loss the biggest obstacle standing in your way is YOURSELF. Excuses can be made every day as to why you shouldn't go to the gym, why you can eat fast food, etc. Start thinking of reasons as to why you should eat healthy today, why that gym trip is worth it. Think of the long term and every step you take, every healthy dicission you make each day will get you even closer to that dream body. Picture yourself as a strong healthy individual and you will start treating yourself that way.
If you want what you do not have, you must do what you have not done.