I'm late to this thread, and have only skimmed the responses, but unless you are dealing with purely mechanical issues, (focus, shutter speed, etc. ) I'd like to make a different suggestion.

Cut two or three big pieces of mat and frame some random prints from your "unsatisfactory" rolls. Hang them each in a different area of your house and tape a piece of paper beside them. Over the course of a week or so, take the time to examine the photos. With the big mat, the images will be isolated from their surroundings and you can really concentrate on the composition and elements in the picture. Take notes on the good and the bad. You may find that some of the pictures grow on you. Or you may be able to identify specific things that detract from the photos. If you can, re-shoot a picture using your notes as a guide. It's not a silver bullet, but it can really help you find what works for you in a given image.

Don't give up. By all means, take time off, but don't walk away from something you love so much.

Cheers,
Tom