Don't feel so bad. I think everyone has experienced this emotion at one time or another. My most tense time in quilting is picking out the pattern and finding the right fabric color to go with it. I audition so many fabrics that when it comes time to putting it all back, I cringe. I am usually very open to mixing several prints and I like to think I am getting better doing so with each quilt I make. However, I have had my moments when I felt burned out and just put everything away for a week or two. It's usually that time I pick up an interesting book (usually a romance novel)to just melt away the stress.
Put the project away for a while and work on something small and fun. Once you have finished it, the joy of a completed project will inspire you to go back to the other project and complete it. Good luck.