Joy, I wonder if you are selling yourself short. Just because you were unable to handle the load at first doesn't mean you are incapable of doing it. I wonder if you have convinced yourself that you are not able to do clinical nursing, when the problem may be elsewhere. Could it be that you have troubles with organization, goal-setting, or planning? I'm certainly not saying you should be in a clinical setting, but I would hate to see you (or anyone else) avoiding clinical work because of what may be secondary issues.
You have discovered that most positions require some minimum of successful clinical practice. I think this is because general clinical nursing allows us to bring together many of the theoretical skills we have learned. (It's one of the reasons I'm a big believer in one to two years of med-surg practice before going to other, more specialized fields). I think that many positions are going to be wary of hiring you if you have a spotty track record in clinical settings.
Have you considered speaking with a trusted nurse confidante (maybe a former teacher or someone of that nature) about your problems? Such a person might be able to point out things that you are not seeing, and give you advice that might help the situation.
Good luck, and, again, don't sell yourself short. Lots of folks have difficulty with the transition from school to practice, and especially with finding the niche they best fit in. Don't feel like you're alone -- use the resources you have, and find where your particular skills and talents can best be used -- for yourself, for consumers, and for nursing as a professional field.
Jim Huffman, RN