I think we've all been there at one time or another. I don't curse very much but I do get royally frusrated at times. A good number of my half-finished quilt tops have ended up in the wastebasket. I should have "unsewed" them and re-used the fabric, but by that time I was hating the fabric as much as I hated the quilt top.
I don't know anyone who can sew a perfect quilt and I think the challenge of completing a top with relatively few mistakes is one of the most fun and/or satisfying aspects of the quilting process.
Please don't quit quilting altogether. Put yours away for awhile but look at every quilting book and magazine you can get your hands on, and chances are your urge to quilt will be back again.