How do you know if the girl you're with is the one you want to marry?
She's enlisting and we're both 20. If I were to marry her now we'd be able to stick together but if not I'll probably never see her again. I really like her, but I'm not sure if I'm ready to marry. I've only known her two years
Don't do it, thats how you end up with three kids you hate and a divorce at 50 cause she was fucking some guy in your bed. You've only been with her for two years, and you're not going to see her for long periods of time. Why would you trap yourself into that? Break it clean while you still can and search for someone else.