Please advise urgent!!

 the  boy has no  option  but to  fight out  case  filed  by your friend Nisha  only after  acquittal  he  can   take  action  only  if the  case  against him      was not bonafide   and   was out of  malice, but mere failure to  prove  does not necessarily mean that the  case  was  not  bonafide   and that it  was    filed out of malice 

I don't think Court is going to ask your friend to marry the boy accused of offence as you r going to marry with some other boy. Main object of law is to do justice and do welfare of women. So if your friend is now marrying someone else and other boy is acceptiing you then i think court will not as for marrying accused.

Secondly as stated by Mr. pandya that it is to be proved that case was filed with malice and not bonafide, then only action lies against your friend.

So if guy gets the stay of proceedings, can he file case against my friend?

If it is a false case filed by Nisha, the boy can file cases against Nisha.

However, most of the time boy would be too glad to get away from criminal charges.