It sounds to me like you are suffering from the usual case of "High School-Idus", coupled with a minor infection of infatuation.
For the first part, you first have to become who you want to be in life. The only restriction that stops people from being anything they want to be, is themself.
The more you decide to sit at home and play video games (Not that there is anything wrong with that, persay) and the less times you decide to actually get out and do things with other people, is the less "social" and "uber-nerdy" you become. Before you know it you are 35 and still living at home, don't have a girlfriend, and are still a virgin.
But in response to this romantic fling you have with this chick:
#1. You don't love her. By your own admission and aparent lack of experience in the relationship department, you have no idea what that word truly means. Sure, you might like her a bit and think she is this wonderful creature, but you don't love her. This is your infatuation.
#2. It sounds to me like you don't even hardly know this girl as much as you are letting on. If you really want to win the little lady over, then show her how much more of a manly stud you are over her current boyfriend. You have to ask yourself, "What do I have that she wants more than what she has now?" If there is nothing, then you will get nothing, plain and simple. You are in High School. Kids go through relationships like they do underwear.
#3. As much as you think you letting "The One" slip away, think again. High School is all about trying to fit in and figure out who you are, and less about what is really important in life. Learning. This includes learning about relationships. This relationship with her and her "boyfriend"? Guess what - It aint gonna last. They will be broken up within a few months and she will be looking for someone else.
#4. If you want to "grow up" a little in life, then start doing it. Get your license. Start standing out and going out a little bit. Let people know there is more to you than some nerdy kid who hides in the shadows. I promise you this - The more confident, mature, and busy you are, the more the girls will notice. The more respect you will have, and the more fun you will have in life.
It sounds like you have a lot of different things that could use some tending to. The #1 thing I would say to you is to sit down and have a heart to heart with yourself, and figure out who you really are, who you really want to be, and what you are going to do to get there. After you do this, everything else will fall into place - Including the ladies.
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