You seem apprehensive of the next step. To make it a committed relationship.
You have stated you have not known her long enough to take the next step of commitment. How old are you both? Do you realize the pressure she is under?
In these six months, what have you understood about her? What more you wish to know? If you can get a clarity on this, you can talk to her and clarify your points. What are your expectations from a life partner? What marriage goals are you willing to build? Have you discussed financial/career/personal goals with her?
Your girl wishes you to meet her parents. Will this help? Meeting does not mean marriage immediately. It means you are committed to her.
In case you are not willing to be committed to her now, you will have to tell her. Also your reasons. Maybe she will help you get clarity.
Your talk may help her to take her own decisions. To wait or not..