It is not allowed for her to marry that man, nor to her parents to marry her forcefully. If she doesn’t want to get married with anyone else, then so be it. If she believes that marrying him is permissible, she becomes a kafir and an apostate.

my aunty is in love with a hindu man and she wants to marry him and that hindu man has refused to embrace Islam but he has promised us that he will always allow our aunty to practice Islam freely and hell never try to convert her to the hindu faith and the problem is my aunty is not agreeing to marry any one else so can my grandparents marry her to anyone they like forcefully?

Apostasy |