First of all, please note that in India, marriages are not done only to a girl and a guy. Its the wedding between two families. So if the family is comfortable with each other the life will be easier.
Legally, there is nothing wrong in selecting a guy of your choice is you are 18 and above. But the real problems start after marriage. The couple who have married in the same community face so many problems, difference of opinions in their life. Think about you. You are of a completely different religion. Your lifestyle, your beliefs, your dressing, speaking, food everything is different. The mindset of people will be completely different. Your husband maynot object and may give you all the freedom but what about his family? It can be really hard for you to adjust with them or for them to accept you in the family and this may lead to lot of problems. You should have thought of all these thinks before itself as you knew your family's reaction very well.
Anyways, happened is happened. Cant change it. You have many options now.. First, leave your family and go to him and get married. This doesnt sound great and who knows your family may try to find u and may lead to lot of problems later.
Second, Try to convince your family. Tell them you can never be happy without him.
Third, forget him and marry a good guy of your family's choice. Time can heal anything.
Option is yours. Think wise, and take the right decision