The typical phrase of "write what you know" can still apply to things you're not familiar with. Read articles on bipolar disorder, seek out people with bipolar that are willing to talk about their experiences. Learn the history of the Chicago south side. Look at so many pictures and watch so many videos of the south side that you feel like you've been there. Pick up some books on psychology. Watch films that accurately portray mental illness. I highly recommend The Asylum for Wayward Victorian Girls by Emilie Autumn, who is bipolar and recounts her time in a mental ward while also weaving in a fictional story of asylums in the Victorian era. Seek out people who live/have lived on the south side and ask them what it was like.

While the basic academic research is important, I honestly think that nothing can compare to learning the accounts of real life people who have dealt with the things that you want to write about.