How to recognize myself

I spend plenty of time trying to understand myself. Trying to understand who I am and how to help myself survive in the crowd. I believe that if I get on good terms with myself, I can get on good terms with the whole world. After reading a lot of books, I still haven't found the answer. Haha, maybe it's my fault, not getting the point of the books. Maybe reading the books is a fault. Sometimes I am very happy when I find a sentence I like or find a thought from others. But when I get nothing on some days, I feel sad and hollowness. I add on other people's thinking and new ideas. Now I face the choice, keep on working the job which I've spent more than 10 years at, or try something new which I like and I am good at. I've found I'm interested in many things, but I haven't found anything I am really good at. How to make a correct decision? I need more time.