I think I can, I think I can, I think I can

Isn't it amazing how everyone seems to have a higher opinion of your abilities than you do, except for potential employers? Does that mean that everyone else is just being nice and you're right after all? Or is everyone else right, you're being to hard on yourself, and the lack of employment is due to other causes? And it's not just prejudiced friends and relatives, but people with whom you have a more casual acquaintance with who seem to have full confidence in you. I try to tell myself that everyone else's confidence means that I am more competent than I think, but then that attitude starts to falter when I can't even get an interview, let alone a job. Perhaps it's just failings in my cover letter writing? I'd like to think so, as that means I can fix it. However, I've had interviews for two different jobs that I thought were perfect and that I really wanted to do, and neither hired me. I'm so tired of this. I just want a job.