The best way to overcome your fears is to tackle them head on. As soon as you confront a fear, it is no longer a fear.
Take the fear of getting your first mortgage, for example. The day you decided to invest your money this way was the day you felt your fear dissipating. Once you set yourself that goal of repaying a certain amount per month, you saw ways to achieve it. And a few years later, you found yourself not only easily repaying the debt, but thinking about doing some renovations.