Lacking Maturity

As we all grow up in the world, we reach different levels of maturity with each year we gain. Since I began high school I have put myself in situations that require a level of maturity I just don't quite have. I went through and grew out of that whole party all the time phase my freshman year...yeah, I'm a little ahead of my time. I understand the depth of situations more so than my peers but that doesn't make me more equipt to handle mature situations. All I can do is analyze and wrap my mind around them.
I guess I have had this forced maturity since I met my best friend as a freshman while she was a junior. I have listened and advised her on situations on conflicts way beyond me, and I loved and currently love it. But there are certain things that I still can't wrap my sophmore brain around. These include having sex with random guys, sucking dick, graduating, moving away, college, and leaving everything I have behind.
Having a best friend who is graduating this year can sometimes be challenging emotionally. It's her senior year, it's time to live it up and broaden as much of her horizons as she can. She is basically all grown up and ready to move on. In fact, she wants us all out of her lives so that she can escape all the memories of her 17 years in our small suburban town. She's ready to move forward with her life and education. It's hard for her to say goodbye to her friends who have been with her since 2nd grade, I know. But at least they're moving on too. To see someone, who is such a major portion of my life, so eager to leave me behind on a whim...I guess it just stings.
But here I am. The little sophomore who just can't handle growing up. And here I'll be for two more years. Like I said, I understand everything, but I still can't cope with some things.