Love marriage complications

I was involved in a relationship with a girl for last 6 years, we were mutually dedicated and committed to each other. however since we were from different caste (me being rajput and girl being a jain), so us time time to convince my parents and girls parents did agree to it at all for last 3 years.... finally beginning this year we started planning for a court marriage. but girl backed out at the last moment and agreed to her parents deciding marry a jain boy selected by them. this leaves me and my family in a lurch who has been waiting for girls family to cooperate for last 3 years wasting our time, emotions and saying no to numerous proposals myself. i can understand the girls point of view who might be under severe pressure from family and has decided to repulse my aproach in every way possible. for the record, ours was a very loving and committed relationship and there was an accidental pregnancy in between as well which may help help you guage our seriousness towards eachother. we decided to mutually terminate the pregnancy since we were unmarried and weren't ready for a baby. now only option that i see is to break the marriage by informing the prospective groom, about all that girls family is hiding frm them. i know it is ethically wring on my part as well, especially since girl has completely left my side and her family is simply refusing to see my side of the story. ps. we are both adults, 30 and 28, working and independant. Only thing working against us is her parents refusal to accept the fact that i am rajput and they threaten girl with suicide if she takes my side... what legal options will i have once i call the groom and tell him about our past because girls family may end up comlaining against me for ruining their reputation