My Girlfriend Does Not Want To Get Married

I do love my girlfriend and she makes me really happy...but I'm afraid things will change if we get married. We're young and we have all the time in the world...why does she always want to rush things? Lately, all this whining has really become a turnoff...I mean it's hard to be loving when someone is always screaming at you. I think ignoring her is the best thing to do at this moment because every time we talk it turns into an argument. In the interim, I have been watching some cool porn movies in the time I would spend with her. I get really excited and am eager to try some of the stuff I've seen...But everytime I suggest something I have to plead with her to try it...and that makes it less enjoyable. We're not even married yet and our sex life has already gotten boring...what will happen if we get married? will she just want to do missionary everyday? I think we should wait....