Well, I guess you have a couple of choices here. 1. You can keep trying. 2. You could ask some one, a trusted quilting friend, who will sew along with you and watch what you are doing that gives you results you are not happy with. 3. You can say, "quilting is wonderful but not my passion". 4. You could give yourself a little emotional break. It sounds like you are being very hard on yourself.
I wish I had "magic suggestions" for you but my wand is bent and the tip is missing. Tee-Hee! If you love quilting, just keep trying and remember that many of us on this site are not perfect quilters. I trust that you have gotten lots of good suggestions from others already. Chin up and quilt on!