Disagree on Marriage

My family arranged one girl for my marriage.After the date finalization we started talking and it was found that she is the perfect girl for me and also well behaved, have respect for elders and seems to be a very well managed housewife.She is very much loveable and also love me so much. But the problem create just 20 days before the marriage.Actually she had a relationship in her past life just few months back.She broke up all those things and trying to started a new life with me. Now the family of her past relationships made some cheap things to showing her few photographs with that boy and tried to break up our marriage às that girl's family was not agreed with her past relationship. They tried to broke up our marriage and after that girl's family would have no other option to accept her past relationship. But the thing is that the girl doesn't want to go back with her past relationship at any cost and she also love me so much. My family doesn't agree anymore for this marriage as she had a past relationship and also there is so many bad rumours about her. Now the point is she is not pressuring me to get marry her but told me that she would have no other option execept to commit suicide or can't live anymore with such scandal. Now she and her family agreed to get marry her with me without my parents agreement. Then I would have to separate from my family as my family would never accept her at this situation. Now if I don't agree to accept her to against my family and by chance she commit suicide as she love me so much also as I do. What would be the legal issues on me if she commit suicide at this point.