Assalaam Alaikum, I am very sorry for your situation, this situation is extremely tragic. Know the following please:
-Women have the absolute right to divorce their husbands for ANY reason, even if it's a blatant thing like they do not find their husbands attractive anymore (harsh but true). Yes divorce is a very detestable thing in Islam so much so that according to hadith the "Throne of Allah SWT shakes" but He has Given his creation that right and under very harsh circumstances there is no problem with it. What is his abnormality if I may ask? Is it some serious mental condition such as bipolar disorder or schizophrenia?
-No valid nikah can take place without the full consent of each participant, so if your father married you to him without your consent or hid the fact about his severe abnormality the nikah is invalid to begin with
-Where do you live? If you live in a western country your situation can be very easily solved as there are plenty of resources here. If you reside in Pakistan/India or wherever I understand your situation becomes more difficult and you may have to rely on your family members for help, if your father leaves you and the family dont worry, Allah SWT Will Provide, have faith in that. Do not prolong this misery if you don't want to, do NOT destroy your life like this, ou will never get this time back and you will always be full of regret.
-Reading Ziyarat Ashura for 40 days consecutively inshAllah solves any difficult problem (BELIEVE ME i have done it and experienced it numerous times) and ask Allah through the Ahle Bayt A.S and call on Imam e Zamana A.T.F.S to help you
-Please do not think of suicide, I know your situation is extremely tragic but believe me there are much worse circumstances out there, inshAllah you will get through this!
-Remember the Ayaats of the Quran "Allah Does Not Burden a soul beyond that it can bear" (2:286) and "So verily with hardship there is ease. Verily with hardship there is ease" (94:5-6) notice that line is repeated twice as in it is being STRESSED to you to believe in that.