I have no sister by my parents. But in my college, I have one sister since one year. As a brother , I love her much and try to treat her as a sister by blood. And I expect a similar behaviour from her , what she don't, I think so. What should I do?

I am not sure what you mean, but I am going to take a stab at this. Is she adopted?

You can't force people to act a certain way. It's nice that you want to treat her like a blood sister, but you can not force her to have the same feelings as you. All you can do is continue to be nice and polite and hope that she returns the favor.

Do you mean sister from college like as in school? Meaning she is a school mate?

The best part of giving is the act itself. The dangers in giving is that it can come back and bite you. So if your treating her like your "sister" and you expect the same from her that is unrealistic. Only if she wants it that way then it is OK. But she is under no obligation to return anything she is given freely. Its her choice.