I have been liking a girl for several years, though she does not want a relationship. what should i do?

There is absolutely nothing wrong with just being friends and seeing where it goes. It may be that she just doesn't like the wording or the pressure of a relationship. I am that way. You may not have to be overly impressive. All she may want is just a friend to hang out with. When I am ready to have a "relationship" or get married, I hope it is with my best friend. Best wishes.