I completely understand how you feel - I was the same! I used to paint ceramics and at one time had a small business. However when I learned to quilt a few years ago, it was like everything I had ever known about colour went out the window! My mind was just blank - I felt like an idiot.
I don't think there's a particular 'secret' other than the courage of your convictions and the confidence to trust yourself to pick what you like and go with it (remember there are no quilt police). This will come with time/experience. Also, your tastes may change over time - happened to me.
Have a look at the Quilt Gallery
here to get some more ideas - there are 8 pages. Also, many selvages have little dots which indicate the colours that will coordinate with that fabric. happy quilting
