Hey, now is your time in your life that you can think only of yourself. If the relationship isn't great, you can get out of it easily (much better than marrying her, then finding out you aren't totally excited about her).
You are in charge of your own money. You can do whatever you like. You don't answer to anyone right now.
Go have fun. Join the military, do something you dream of doing (travel, whatever). You can be risky right now, in ways you can't when you are responsible for a wife and perhaps kids. Enjoy life to it's fullest.
College is a great thing....