Good Morning Washu and welcome to what we affectionately call the "nutty boards". You ask some good questions. While I am not a medical nor legal expert by any stretch of the imagination, I will try and see if I can give you some ideas.
One of the things our President supposedly was going to work on when he took office was an way to make prescription medication more affordable to people. I think he was primarily gearing this for seniors, but it may very well apply to others. It hasn't happened yet.
At this time, there are private health plans in existence. Some may or may not cover your depression. They might deem this a pre-existing condition. I have switched health plans over the years and have never had a problem with getting my depression meds covered. ( I was diagnosed 9 years ago). One place to get medication is from your doctor. They have tons and tons and TONS of samples. If you explain to your doctor your current financial position, that you had to stop taking meds, she/he may provide you with enough samples to last awhile. Another way to get help would be to be declared disabled, but that would mean your doctor would have to diagnose you as such. I believe Disability Insurance is a state run program ( at least it is in California) and things can vary drastically from state to state.
As far as legal protection, I am not sure I understand the question. Are you saying that you believe you were let go due to your depression? I think that in order for you to be protected, your depression would have to be declared a handicap... like deafness and blindess.. etc.. It is illegal to discriminate in employment based upon certain disabilities. There are all sorts of legal qualifications and determinations on this, so it isn't as cut and dried as it seems. I may be wrong here, and hopefully a legal eagle will be along to correct me, but I do not think at this time in our country depression is classified as a handicap.
Your doctor is the best resource for you to start with. Yes, it will cost you the dollars it takes for a visit, but I think it would be a wise investment. If you just call your doctor, I think it might be easier for them to say no to your request for free samples.. since you aren't there and the phone tends to de-personalize things.
I can really empathize with the cost of medications. I am carrying my own medical insurance right now, since I am a contract employee. Times are very tough in the job market , so try not to take being unemployed as a personal relfection upon you. The question isn't IF you wil get a job, it is WHEN. You eventually will get a job.. it may be a week, it may be a month.. or more. Try temp agencies. I hope you have already filed for unemployment insurance.
Good Luck and keep posting. During the week, we have a "Daily" thread.. a new one for each day. I hope you'll join us there.