This is why "diets" fail. When people think of something as "temporary", it won't ever really work. You are right- you have to change the way you live to make it stick. It's your new, healthier way of life, and it's not temporary.
I have had to change the way I eat for health reasons, and it was hard at first. But, once I got in the mindset of "this is how I eat", then it became easy.
I'm glad that you can see your new lifestyle as permanent!