Misuse of sc/st act

1.One of the known sc caste member took loan from me by writing a bond paper 2.later the given time duration is finished he didn't return my moneyback 3.so that every time when I went to his house to ask money he would say something or other reasons and he will say that he will pay next month almost a year has finished he didn't pay me 4.for any emergency I signed in my blank cheque and kept at home as he is known person I don't know how the cheque went to him and the cheque got bounced and filed case against me 5.later I went to ask about the loan amount and about cheque that how did he get my blank cheque he talked in a rude way and even I got angry and scolded him for cheating me but I didn't use their caste name or discriminate them or their caste 6.next day two more cases filed against me 7.the first case was filed by the person whom I gave loan saying that I discriminated their caste and filed case against me on sc/st caste 8.the second case was filed by his wife saying that since she is a low caste I harassed her by pulling her saree which was a very big lie said by the husband and wife and filed case against me. 9.now they are demanding for 5 lakhs for insulting their caste which I didn't 10.now how can i come out of these fake cases placed against me 11.I wonder how they are lieing and use their caste in between 12.In this case even they don't have proofs that I discriminated their caste and pulled his wife saree.even I don't have proofs for proving that I didn't discriminated their caste and proofs to prove that I didn't harassed his wife. Now I am tensed they are using sc/st act without my fault.I think even court supports sc/st act Now how can i prove to the court that I didn't discriminated their caste