Rum bro, Just ask your parents, if you marry someone from your cast, can they give you a guarantee that you will be more happy with her than your intercast girlfriend. I don't think they can give you this guarantee. But you can give them that guarantee because you love her and hopefully she does too :) Besides, respecting parents doesn't mean you marry someone from your cast and sacrifice your love. Respect is not show off, this is something that you feel for your parents. Your respect doesn't vanish just because you marry someone you love. It's a shame that we have to discuss this issue while living in 21st century and getting educated in the US. The matter could be serious if she was from a different country, if she spoke a different language, if she had a totally different religion, if she had different values, morals, cultural expectations and so on. Is there anything different in your case other than her last name? Think about it dude. Respect your parents, we all should, but do we have to prove that by sacrificing your love for some stupid cultural belief created ages ago by some racists? You might as well stop shaking hands with other Nepalese people before asking their last names, who knows, if they are from very lower cast. Your grandma could get pissed in Nepal.