Deborah, I have been quilting for 3 years, and this color selection has not gotten any easier for me. However, I now allow myself to enjoy the process, rather than being frightened of it. I am no expert, for sure, and probably never will be. I do try to make sure I have darks, lights, and mediums. And when I am in doubt, I go with different shades and fabrics of one of one color. That always pleases me. I know I still tend to "match" fabric too much, when often I should be looking for a contrast. I envy those more experienced who just "know" when a fabric is right. I never know, and I can't visualize at all a finished quilt by looking at fabric. But, like I said, I am now enjoying the process when it used to terrify me.
You will get better at it, and if that doesn't happen, you will just get more comfortable with it.
Dina