My question involves a roommate in the State of: Indiana

I recently signed a 12 month lease with a long time friend. Her father paid the entire 12 months lease in full upfront and we established a verbal agreement that I would pay them half of the rent monthly as if we were splitting rent. My room mate recently also got out of an abusive relationship of 2 years and was clinically diagnosed with PTSD, bi-polar disorder, and post-battered women's syndrome. Upon moving in with her, I was not informed that she was not on medications or seeing a therapist or counselor regularly. My room mate since I have moved in has been verbally and emotionally abusive to me; making threats (including threats on my life) for very small and minor things. She brings men back to the apartment and engaged is drunken casual sex and then denies that it ever happened when I can hear these events occuring in the room next to me. She is demeaning and irrational to me, very controlling and dictates to me what will be done in the apartment with no compromise. I have informed her that I am moving out, however she has threatened to take me to court and sue me for the months rent that I will not be living there after breaking my lease with the apartment because her dad paid the rent in full; she claims that because of the verbal agreement I owe her half of all the rent money even though I am leaving for my emotional and psychological stability. Am I obligated to pay under this circumstance?