Christian growth and the process of maturity

Why is it taking me so long to grow as a Christian? I've been a believer for a while, and I have to confess that my lack of spiritual progress has really got me down. When I was born again, I thought life was going to be beautiful from that moment forward, but several years later I'm still not the person I want to be. I don't feel God's presence the way I did at first. I know in my heart that fear and selfishness are holding me back from loving other people as well as I should. What's wrong with me? Am I truly saved or not?