Its a false assumption. Its like a guy fretting about the girl of his dreams walking away and not talking to him. If she was the girl of his dreams, she wouldn't have walked away and she'd want to talk to him, DUH. (I just read something that made me think of you as a girl. I wrote this with a guy in mind, so substitute pronouns where appropriate, it still works.)
Being desperate means you make things seem more important than they are because you want them to be important so you can stop looking for it. For most people, being alone is worse than being in a bad relationship, although being alone at least means you aren't fooling yourself into thinking you're someplace you actually aren't. A pile of garbage, a pile of nothing, and a pile of kittens take up the exact same amount of space but unless you're allergic to cats, you don't want to sit in a pile of garbage if you can't find a pile of kittens to sit in.
So what does this have to do with confidence and all that crap. Even Bill Gates started off as a failure (a dropout of Harvard, how much bigger a social loser can you get?) Doesn't mean you will end up as Bill Gates but even rich people put on their pants one leg at a time. And successful people don't accept jobs that don't arrive or girls who walk away from them as being a measure of their success. If you didn't get it, it's because better is out there. Think small, dream small, achieve small, blah blah blah.
If you are unhappy with crap, its because you are SUPPOSED to be unhappy with crap. You can't make someone love you or someone else want to hire you if they don't want you. And if they don't want you, do you really want to be with them? One-way love is bad in relationships and its bad in business, too. A dream job is alot like a dream relationship: the love goes both ways. Your dream job doesn't pick someone else, they WANT you as much as you WANT them. You've been selling yourself short for jobs for so long, you've come to expect crap. Loving the field you are working in and loving the company you are working for are two different kinds of love, and right now you are confusing the two. Yes, your dream job will involve a company but that doesn't mean every company is or even could be your dream job. If you've failed in any way, is it because you didn't make the cut or because it wasn't a cut you actually wanted to make in the first place, but couldn't admit it to yourself.
There was no Apple to love until Steve Jobs decided to fail by walking away from whatever company thought to hire him. Successful people know to walk away from 'success' in order to achieve the actual success they are looking for. You can sit and moon over your 'dream job' or you can buy a really nice outfit so you'll have it ready when your actual dream job actually does invterview you.