My friend, it is common problem with lovers. Some time you need to stnad for what you think. If they don't agree you have two options, 1. Courage...get married yourself ( I hope you both are adult and you are in good condition as per job to survive). 2. Put your feet down.
I have been through this phase and I opted first option, I am male and here it was opposite, my parents were not ready. I stood by what I felt right. It never means that you never care your parents but you are strong enough to think what should you do. If your GF doesn't agree then sorry you are left with option 2 only.
