Why do I mourn that "this" is forever?

Why do I mourn that "this" is forever?

I will have to watch what I eat forever. I will have to keep a steady exercise routine forever.

Why is this a big deal? Why do I only think about the jealousy towards others who can eat / do whatever they want and not gain weight?

I have made a conscious effort to change my perspective. I am a 32 year old woman. I know what happens if people don't eat a healthy diet and exercise. Those medical ailments are a lot more frightening than LOOKING overweight. They can take your life. I know how good I mentally feel when I'm in control of my health. I know that good food can provide all the power I need to keep me happy. I know the energy it provides me, I know the confidence working out provides me.

I love these things. If I become happier with my physical self, that is the bonus - not the motivator.

This is forever. It's forever for me. And there is nothing to mourn about.