You should be disheartened. It's a miserable process because it seems so hopeless at times. There's really nothing wrong with being miserable in and of itself. It's a perfectly normal reaction to your situation. Just don't let your miserableness turn into a depression that keeps you from doing what you need to do. Study for the bar, take the bar exam, and then start looking for a job.
I'd second Dr. Balsenschaft's advice, and further point out that Dr. B's advice is entirely on point for the situation right now. You're depressed about having only California options. Nothing wrong with being disappointed at what's transpired so far. That's a reasonable response. But you can't let "feeling glum" stand in the way of actual progress.
According to your prior posts, you've been diligent about rustling job prospects. Assuming you followed Dr. B's advice, you made a note of all the firms who wanted to talk to you after you received your bar results and you've already zipped off friendly "remember me?" e-mails to them all. You've networked, schmoozed, asked everyone who knows anyone to talk about you, etc.
If it's true that you've shaken the bushes and trees in Chicago, doesn't it seem sensible to move to try something new? Work at your brother's firm. You can do a lot more than glorified paralegal work -- you can do everything but sign the pleadings and argue in court. So, research, write, talk to clients, negotiate with opposing counsel, learn the law, learn how the legal industry really works, meet people, make friends, and have something substantial to add to your resume.
You can always return to Chicago after you've "done the west coast thing." No firm will question your geographic loyalty. If there's really any doubt, work out a deal where your brother's firm has a collegial relationship with an employment firm in Chicago. Then, there'll be cross-referrals and joint articles and any number of ties that will keep your resume full of Chicago. I don't think that's necessary, though. The best thing for you to do is add something new to the package that you present employers and come back to try again. Coming back is proof enough that you really want to be in Chicago.
You've expressed a lot of concern about your debt, especially. You don't want to run out of deferment time when there's a real solution right in front of you. It's okay to feel bad about where you are -- but keep putting one foot in front of the other, despite how you feel.