"but at last I told ‘ la aba timi ra ma biha garau, garne ho?’ she laughed loud .....................Somhow I could clearly sense that she liked me."

what did she say about your proposal? she only laughed and that's it? If that is the case she only likes you as a friend. Possiblilities may be the following:

1. she says she loves you but won't marry you because you are not punditji and her parents won't accept and she cares about their feelings: real meaning she won't marry you but don't want to hurt your feelings.

2. You know she likes you and likes to spend time with you: We men are wired to think and hopelessly hope that like = love. This won't be the first time and you won't be the first person to have this misunderstanding and to top it off be in denial about having any misunderstanding.

3.  Have you said that you love her and want to marry her, literally and not casually? Maybe you need a reality check. A lot of times we want something so bad we start living in a alternate reality and feel that everything is going according to our wishes except for this little one thing, which in your case is "the devil bahun thing".

4. And lastly, you said you cannot marry her because it will hurt her parent's feelings and consequently hurt her feelings. What about your feelings? And what about her feelings being hurt because she loves you and cannot marry you? It seems like she's gonna have a "hurt feeling" regardlessly. Go figure!