Maybe instead of being able to enjoy your peace and happiness, you are worried and anxious about
that happiness being taken away from you? Try to remember that life is ups and downs of emotion, struggles and success. In wanting to be "cured" of my depression, I sometimes fall into the mindset that once things get better, they will stay better, and for the most part this is true, because a big part of coming out of depression is being better able to handle the pitfalls of life. But I have to constantly remind myself that feeling happy all the time isn't normal for anyone, and that I will still have my sad days too. It's just being able to handle those sad times and knowing things will turn around again is the new goal.
Smile because you're a beautiful soul and life is good!