Is it normal that i love straight porn but not interested in girls?

I'm a guy and I've been in a relationship with a girl for about two years now, and we've had sex a couple of times. However, I masturbate a lot, and she knows it (Long distance). But whenever I do, I don't really think about her when I do and I watch porn instead. But the thing is, despite doing this about everyday, I would never talk to girls in public. I've turned myself off of them for so long that I completely have no desire to have even a friendship with a girl. I love my girlfriend very much and I still find her attractive, but I feel like if we ever break up I would never date again because I just have little interest in girls. Never in my life have I ever walked up and "hit on" a girl (ask for her number, compliment her, whatever guys do nowadays.) I'm in college now, and I've noticed many guys are focused on getting girls into their dorms, but I really do not feel that desire at all. Even if I wasn't in a relationship, I know that I still wouldn't. At the same time though I know I'm still attracted to girls because I watch and enjoy porn with no problem at all.