Failure is not making a mistake, it's not picking yourself up after you make a mistake.
We all have these moments Kevinnader.
Just pick yourself up and start over. Eventually, eating healthy will become a habit and you will no longer have an interest in unhealthy foods. After a certain point you will even get sick if you try to eat them.
If you keep on eating good foods you will begin to naturally crave them. I sure do.
Don't beat yourself up. Just keep on trying and eventually this new lifestyle will become very easy for you. Cravings will come, it's a detox process and your body is experiencing withdrawal from poisons. Sugar is a drug, you will get hooked if you eat too much of it and you will have withdrawal symptoms if you stop.
It usually takes about a month or two for most people to stop having cravings, so just know that you have that to look forward to.
What I used to do if I had a craving for unhealthy foods is I would eat something that was similar to what I wanted. Like if I wanted Sugar I would eat fruit. If I wanted something fatty I would eat an avocado. This can be difficult to do at first but if you can find the strenght to do this 3 times in a row everytime you have a craving, it will become a habit and you will no longer reach for the junk food.
You are beginning to experience what it's like when change your lifestyle to support perfect health. Be very proud of yourself for taking charge and making changes. It's a bumpy road for all, but if you follow through it's always worth it.