Hi Vassiliki,
Thank you for posting this interesting, intricate topic.
Prior to making any suggestions, I think there are several things that need clarification.
1. In what ways does Epictetus define wealth? Is it material, emotional, or both? How would you interpret this quote?
2. If you are unhappy with your life, then either you need to change it to make it better, or you hold the belief that unhappiness lies within you and you should find ways to heal your heart and mind. Which one best describes your situation?
3. The picture you have of yourself does not seem to be a positive one. You blame yourself for feeling underappreciated. is this an idea that you developed yourself, or has it been imposed upon you by others? (e.g. friends, family, culture)