You have a decent case, but you have a huge problem because you have not established the right "paper trail" of treatment. It is obvious to me that you are seriously depressed. People with less mental impairment than you get approved for disability all the time. But you will get turned down because you haven't laid the foundation. You need to see a psychiatrist. Social Security pays much more attention to a psychiatrist than to a psychologist. They won't consider you to have a mental illness, if they don't see where you have been on psych medication.....
Good luck.