My girlfriend and I are in love and that is special to me. She always treats me right and makes me feel really unique. She is really smart and out going. Not going to lie though, the biggest urge as to why I have this feeling is because she is so gorgeous. I mean, I cant even look at her without being aroused almost immediately. Her face is perfect and symmetrical, she has nice breasts, and the best thing is she has nice hips and a bubble butt. I think it is greedy of me but another reason is to keep her forever.

If you're wanting to create a human for any other reason than wanting a child is fucked up in my opinion.
I understand the mentality of wanting ro start a family with someone that you love. My husband also wants kids, but make sure that you're doing it for he right reasons OP. Those breasts and hips won't look the same once they've created a fed a human being.
However in my experience while I've dated a number of girls it's very rare to find a genuinely beautiful girl that you have a great connection with-so if you have that, then marry her.
I look back now and realized I should've done that with one or two strikingly attractive girls I had the good fortune of dating.
Now I'm older, much less attractive than I used to be and I just don't get those kinds of opportunities anymore. Had I known my true worth when I was younger, I would've banged hundreds of girls.
Yes eventually her looks will fade-so what, that happens to all of us. Just make sure she's the kind of girl you could still love when that beauty has diminished.
You can't just get with a girl to have kids. Your a guy, you don't know pregnancy pain.