Why does my girlfriend pay little attention to me?

From my experiences, it typically means she was interested, then became bored & wanted something else. Often something women do too much. If she feels she knows all there is about you, she most likely will become less interested. Sadly women are a lot like cats. Try to pet them & they may let you at first, but become annoyed & want space. Ignore them & they come looking for attention asking why aren't you petting me. Guys are basically dogs when it comes to 'relationships' & not getting a hook up. We look for companionship & want attention. Can you imagine a cat wanting to pet a dog? As dirty as it may sound. In some cases the girl is cheating, or has thoughts about someone from work or some encounter you weren't aware of. So their mind shifts to who they are thinking of & you're just not it... The best thing you can do, & it may sound bad, but ignore her.... acknowledge her yes, but stop caring where she is & what she does. If she is going to give you little attention. Give her just as much as she gives you. & When she gets all offended. You can say, well, this is how you've been treating me. Don't forget to ask what if anything is wrong. So you can later bring it up that you felt like she was less interested. You can quote yourself having said, hey, I thought something was wrong between us... you shrugged it off. If this girl is in her teens, then you shouldn't expect much from her. She is going to just be a typical teenage girl with her mind scattered even more. If she has some years under her belt beyond the drinking age... then she is mature enough to actually reciprocate adult actions of simply paying you some attention. Teen-Dump her & find someone more mature if her childlike behavior bothers you. Adult, try giving her what she gives you.