Here is what you do:
Get your shit together and improve in every way possible! You thinking your not good enough for her is total bullshit! You can get whatever you want in life as long as you work for it!
Watch this video please:
http://www.youtube.com/watch?v=lsSC2vx7 ... re=related
That is the mindset you need to have in life, never give up man, your 19!
Her relationship WILL end, i can ensure you that. But when it does are you the best man you can be or still the wussy who she sees as a friend?
Step it up and do not contact her anymore, she made her point. Contact her again when her relationship is over and your the best you can be.
In the mean time i will ensure you that there will be a girl who is even better then her and will make her fade away, there millions of great girls out there and you only seen a few of time.
So work on your inner game and never give up!