Advice please? I don't know what is going on nor what to do

[joohyun]

Ok, here I go. I have been dating my girlfriend for over a year and a half, we started good in the honey moon stage till the summer hit. I am her first everything, first boyfriend, first kiss, first everything and, like she said, one the first guys who are not part of her main group of friends that she really got attached to. Her and her family moved away so we became long distance. School started up again and now that school started, she is living away from family. She has been stressed from academics working really hard to meet a certain mark.
The summer, we hit a dip, having painful quite nights not talking and miscommunication, etc.
School started up, it was great. We get to see each other more, she became more lustful and got to do it more often compared to the once every two months when we started dating.
But as soon as October hit, everything went to hell. She started saying how she dislikes the girls I hang around, even the ones that I considered to be so close that they are like sisters to me, didn't want me to talk to them. She would start being more clingy. Become both mad and sad when I am not with her but yet she goes out with her friends. Become more emotional when I say even the smallest thing and disapproves and becomes either extremely mad or sad. She becomes more lustful whenever we are home, especially when I am working or playing games (pretty much every time I play games, rarely get to play my APB Reloaded any more *sad face*).
Here are the last two situations.
Yesterday: We had some spare money to spend for online shopping and split it so we both have $10 on anything we want. She is decided on something for herself and I decided on a dress for her. She got mad because she said she wanted me to get something for myself, and that was. I really wanted to see her in the dress and told her that I think she would look very beautiful in it, and then she got more mad.
Today, is what pissed me off. I was waiting for her after school and waited about 10-20 minutes where everyone was already gone and I was just awkwardly standing there. I have been doing this for the past year and a half, sometimes my friends would wait there with me but not lately. She comes done and says "I'm here, sorry to keep you waiting", and I responded "It's okay, don't worry about it, I'm use to it" and then boom, she is mad. I asked her what and all she says is "You're use to it?" and that is it. She then left to go shopping with her friends. I have not talked to her since that moment so ***?
What is going on? Someone please explain what may be going through her mind and what you think of this and the relationship standing

[basilandthyme]

My prediction: she will continue to get more negative and needy. You will eventually get fed up and leave. And you'll date many more people in your life

Enjoy your teens while you can - and don't get bogged down with someone who's not right for you.