Cardiac Management

Ok...now I've got your attention...was in an emt class this evening concerning cardiac management. In plain terms, a heart attack. But I got to thinking about the emotion matter of the heart. Who's job is it to be concern about the emotional side of our heart. What happens to the person who has been broken hearted? Why does hurt feelings effect us to the point of losing heart? God talks to us on the spiritually level and I'm always reminded of the verse I learned in Sunday School "Thy word I have hid in my heart, so that I may not sin against thee" I know scriptures...I've memorized scriptures but I still struggle with false beliefs. I've been wondering lately if that makes me a bad christian or is that part of growing deeper with God? I can remember the first time I really understood what sacrifice Christ did and what love God must have for everyone -- even me. But how do I get that joy of being peaceful with God? I really want to be reasonably happy in this life. I don't want to live on the sidelines like I have this past year. Changing that attitude is hard becuase I'm so afraid of being hurt again or really failing big time.